Growing
Important Rhododendron Growing Guidelines With Expert Katrina Clow
IN THIS GUIDE Overview Common Varieties How To Grow Rhododendron Rhododendron Care References Rhododendrons can come in many shapes and sizes and can be good choices for gardeners with acidic soil. While some rhododendrons are invasive and not the best choice for eco-friendly spaces, many can be good choices for UK gardens where the required growing conditions are readily available. We’ve collaborated with Katrina Clow, Hon. Secretary of The Scottish Rhododendron Society, to help advise our rhododendron growing tips. “There are so many and in such variety,” says Katrina, when asked why she is so passionate about growing rhododendrons. “They have stunning foliage and the flowers come in every colour you could imagine.” Rhododendron is a large genus with over 1,200 natural species – and many more cultivars besides.1 It is in the Ericaceae (heather) plant family.2 Overview Botanical Name Rhododendron Plant Type Shrub Native Area North America, Europe and Asia Hardiness Rating H5 Foliage Evergreen (mostly) Flowers Varied colourful flowers When To Plant October / March to April When To Prune After flowering Rhododendrons are often evergreen, but can also be deciduous. The centres of diversity are in Asia, though rhododendrons are also native to parts of North America and Europe.3 “Rhododendrons are mostly native to the Himalayas and were introduced to Britain in the 18th century, hybridising since then,” says Katrina. Rhododendrons are usually shrubs, though they can also be trees, and vary considerably in size from less than 1m in height and spread, to up to (more rarely) 30m tall. Most of the rhododendrons commonly grown in UK gardens are medium-sized to large shrubs, but there are also smaller options that are popular choices for container growing. “They love the west coast of Scotland as we get high rainfall and humidity,” explains Katrina. Common Varieties We asked Katrina about her favourite rhododendron varieties to grow. “This is a very difficult question, as there are so many,” she says. “When first growing rhododendrons, you are probably attracted to the most brightly coloured hybrids, but, gradually, the charm and beauty of species rhododendrons overtakes the glamour of hybrids. “They do take longer to flower but worth the wait. “Evergreen azaleas, yakushimanum hybrids, compact hybrids and tender fragrant rhododendrons are my favourite choices.” R. luteum “A particularly striking rhododendron for me is R. luteum with intense yellow flowers, often borne before the leaves form. It is one I associate more with sunnier positions too,” says Horticulturist Peter Lickorish. “However, this and some of the other species, including R. ponticum, are classified as non-native invasive species and must be managed carefully to make sure they do not spread beyond gardens. “In some woodland, rhododendron is so fast-growing that it stops light reaching tree seedlings and lower woodland plants.” Rhododendrons are often divided into spring flowering options, which flower up to the end of April, and later flowering varieties. R. barbatum Some common early flowering rhododendrons are: R. barbatum R. calophytum R. ‘Christmas Cheer’ R. ‘Cilpinense’ R. ‘Countess of Haddington’ R. dauricum ‘Mid-winter’ R. fulvum R. grande R. ‘Praecox’ R. ‘Ptarmigan’ R. arborescens Some common late-flowering rhododendrons are: R. arborescens R. ‘Corneille’ R. ‘Cynthia’ R. decorum R. ‘Dopey’ R. luteum R. occidentale R. ‘Polar Bear’ R. viscosum R. ‘Winsome’ These really are only a small fraction of the many options that you could consider. “Species rhododendrons may take several years to flower but they are definitely worth waiting for,” says Katrina. “Hybrids, in general, are tougher and will flower sooner.” How To Grow Rhododendron Rhododendrons should usually be planted in either October or March to April. Most rhododendrons are a good choice for a partially shaded spot, either below trees (though not in deep shade) or along a border in your garden. Larger options work well in a woodland garden. However, most species and cultivars will be able to cope with a brighter and sunnier position as long as they are sheltered from any winds that are cold and dry. Dwarf alpine species of rhododendron can usually tolerate full sun and will work well in a rock garden as long as the soil remains moist, whilst compact hybrids can be grown in containers. It is best to avoid planting rhododendrons in frost pockets or anywhere where they are exposed to the sun in the early morning. “They can be grown in woodland gardens but they do require an acidic growing medium, so gardens with chalk or very free-draining conditions will not favour them,” shares Katrina. As Katrina explains, most rhododendrons require an acidic soil or growing medium, with a pH of between 5-6. The soil should be moist yet free-draining and rich in organic matter. Rhododendron Care Soil Before planting a rhododendron, it is a good idea to spread a thick layer of acidic organic matter over the soil. You should also mix organic materials into the planting hole that you have created, blending it well with the excavated soil, before firming it back in around the shrub. Soil that is not acidic will have to be amended if you want to grow rhododendrons. However, it is generally best to plant for your soil type and to grow acid-loving plants in containers if you do wish to grow them, as Garden Designer Kate Gould explains: “The great thing about growing in pots is that you can control your soil. “Say you were gardening on chalk and you wanted to grow a rhododendron, you could do so in a pot because you could fill it with acidic soil.” If you are growing rhododendron in containers, make sure that you use an ericaceous, peat-free potting mix to fill your pots. Peat-free mixes can work well for rhododendrons, but to avoid compaction issues, it is best to repot every other year into a fresh potting mix. Watering Rhododendrons have fairly high water needs and will tend to grow best where there is high natural rainfall and will grow less successfully in more arid areas. Make sure that you water regularly during dry periods, especially when growing in containers. “Flower buds begin developing in late summer, so moisture is particularly important – and sometimes in short supply – at this time,” says Peter Lickorish. “Keep plants moist, but not waterlogged,” Katrina simply states. Try to use rainwater rather than tap water to water your rhododendrons whenever possible. In hard water districts, tap water can be too alkaline and can reduce the acidity of the soil. Feeding & Fertilising Renew the acidic mulch around your rhododendron each spring, making sure that the soil or medium below is moist before doing so. It can also be beneficial to change the top 5cm of the growing medium when growing your plants in containers each winter and to feed the rhododendron over the summer months with an organic liquid feed. “Often if the soil is not acidic enough for their niche preference, leaves will turn yellow between the veins as they lack iron,” adds Peter Lickorish. “Liquid feeds with an iron content can reduce this damage.” Propagation Propagating rhododendrons is not an easy job for novice gardeners. However, it is certainly possible to obtain new plants from those you already grow. The most important thing to understand before you begin is that only some species of rhododendron will come true when grown from seed. Named cultivars have to be propagated by means of semi-ripe cuttings or through more complex methods like grafting or layering. Taking rhododendron cuttings is typically the easiest propagation method. Cuttings are taken from the current year’s stems, in late summer or autumn, once the bud has developed fully. The cuttings should be taken with a heel and the stem should be wounded slightly to encourage it to take root. Cuttings of evergreen rhododendrons can also be taken in July or August. Deciduous rhododendrons are more difficult to propagate from cuttings, which is why this is usually only done in a commercial setting. For species rhododendron which will come true from seed, seeds should be sown in January indoors, with the seeds left uncovered on the surface of the growing medium. These pots should be placed inside a heated propagator. Pruning Pruning is not usually required for rhododendrons. You may simply prune these shrubs to remove dead, damaged or diseased material and can deadhead spend flowers to improve the shrub’s appearance if you want to. “Deadhead to get good flowers the following year if you want to improve your rhododendron shrubs,” shares Katrina. You can also prune back many rhododendrons to restrict their size after flowering. Rough-barked rhododendrons will tend to respond better to hard pruning than smooth-barked types. “Pruning too late, such as in the autumn, is likely to significantly reduce flowering the following year,” according to Peter Lickorish. “Often it is preferable to prune in early summer, as long as flowering has finished, and reduce a third of the longer stems each year to restore an overgrown plant back to manageable size. “Aim to prune to a bud if possible. If you do prune back harder, be sure to mulch and water well afterwards to ensure strong new growth.” Common Problems Many problems you may experience with a rhododendron shrub are likely to be due to environmental or care issues rather than pests or diseases. For example, non-flowering shrubs may not produce blooms because of under-watering or improper pruning. Leaf drop may also be caused by a lack of water, waterlogging, extreme exposure to cold or another environmental issue. Nutrient deficiencies can cause issues like the yellowing of leaves. However, common pests and diseases can also affect rhododendrons. Common pests include vine weevils (especially when the shrubs are container-grown), leaf-hoppers and scale insects. Some rhododendron diseases include azalea gall, bud blast and honey fungus. Companion Planting “Anything you like that looks comfortable and enjoys the same conditions as your rhododendrons can be planted with them,” says Katrina, when discussing what to grow with rhododendrons. Some of her favourite plants to grow alongside them include: Snowdrops Daffodils Species tulips Erythroniums Trilliums Primroses Meconopsis Lilies Hostas Small ferns Conifers “Shrubs that like ericaceous conditions, such as enkianthus or kalmia, and trees which create light shade, like magnolias, will add structure to your planting,” Katrina adds. “There are many beautiful Rowan cultivars with different coloured berries and autumn leaf colour which can also work wonderfully. “I also like to add hydrangeas for later flowers.” References 1. About Rhododendrons. (n.d.-b). Rhododendron Species Botanical Garden. Retrieved March 23, 2023, from https://rhodygarden.org/our-plants/rhododendrons/about-rhododendrons/ 2. Rhododendron. (n.d.). University of Bergen. Retrieved March 23, 2023, from https://www.uib.no/en/universitygardens/135136/rhododendron 3. Rhododendron. (n.d.-b). Global Conservation Consortia. Retrieved March 23, 2023, from https://www.globalconservationconsortia.org/gcc/rhododendron/
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How To Prepare And Sow Buddleja Seeds For New Plants (They Should Grow Very Fast)
IN THIS GUIDE 1) Prepare The Seeds 2) Sow Your Buddleja Seeds 3) Place In A Suitable Spot 4) Water Seedlings Regularly 5) Pot On Into Larger Containers 6) Care For Establishing Plants Buddlejas are renowned for the brilliant little flowers that they produce in profusion all summer long, often on conical spikes or panicles. Buddlejas are long-lived perennials, with most varieties being deciduous. As such, once you have grown a young plant, you are sure to enjoy many years of pleasure from it. If you’re wondering how to obtain a young buddleja shrub, then this is the guide for you – simply follow these steps: Prepare the buddleja seeds before sowing, ensuring they have spent an adequate amount of time below freezing point. Sow the seeds in a tray with modules filled with a damp growing medium. Place the tray in a suitable location – a propagator can be useful for providing the right growing conditions. Regularly water the buddleja seeds. Pot on and care for the seedlings, especially in the early stages of growth. Provide the right aftercare for your buddleja, guarding against frost before transplanting into open ground. This process is explained in more depth below. Difficulty Medium Equipment Required Gardening gloves, sprayer, small watering can, hand trowel When To Sow April 1) Prepare The Seeds Buddleja seeds need to be prepped before they can be sown, as Horticultural Lecturer Peter Lickorish explains: “Harvest spent flower stems in the autumn and place these in paper bags, or even better hang them, to let seeds to drop out.” In the winter, place the seeds in a seed packet or envelope if they are loose, then place them in a plastic bag. This should be kept in the freezer for 4-5 weeks. Two months before the last expected frost, remove the plastic bag and keep it in a cool place. 2) Sow Your Buddleja Seeds About 2 weeks before the last expected frost, take a modular seed tray with compartments and prepare it with a seed starter compost mix. Water so that the medium is damp, but take care not to overwater. Buddleja seeds have excellent germination rates, so only sow 1-2 per compartment. These seeds need light, consistent moisture and humid conditions to germinate. However, they are very small and lightweight, so watering might move them about. Therefore, to sow, gently nudge the seeds into the medium, but do not cover them. Thoroughly dampen the medium using a sprayer, or alternatively, water with a small watering can. 3) Place In A Suitable Spot Place the tray near a window where it will receive ample filtered, but not direct, sunlight. The ambient temperature should be around 21°C. What will be lacking in UK conditions is sufficient humidity to ensure germination at high rates. To simulate these humid conditions, improvise a low-rise tent or propagator lid over the seed tray. With the support of pencil stubs placed at the 4 corners of the seed tray, put a piece of cling film or a clear plastic sheet over and around the tray. 4) Water Seedlings Regularly Water the tray so that the medium is kept consistently moist. Watering may be done by heavily misting with a spray bottle or sprinkling over water with a small watering can, making sure to keep the rose close to the tray. “Watering young seedlings without dislodging them can be tricky,” shares Peter. “I find it easiest to place a tray or pot saucer underneath and part-fill this with water, allowing the seed tray to soak up the water it needs for a couple of hours. “Then, lift it from the water, allow it to drain, and finally return it to its original position.” The seeds should germinate in about 20 days. Once they do, remove the cling film. As the seedlings grow, start to expose them to morning sunlight. 5) Pot On Into Larger Containers After the seedlings have put out 4 true leaves, they are ready to be moved into individual pots. Prepare the appropriate number of small pots with any potting mix, prise out each little plant’s module with its soil ball from the tray and repot into a container with drainage holes. “If you have to handle the plant, hold only the leaf and not the stem, as damaging the stem could be fatal,” warns Peter. At this early stage, keep the plant where it is sheltered from winds and in partial shade. “It is important to gradually wean plants off from indoor conditions to the harsher weather outside,” Peter shares. Keep watering the young plant every other day. Gradually decrease the amount and frequency of water and start to increase the plant’s exposure to sunlight. 6) Care For Establishing Plants When autumn comes around, be sure to guard against frosts and wind. Although the vast majority of varieties are hardy to H6, even mature plants should not be kept in an unsheltered spot or exposed to hard frosts. Most buddleja varieties are incredibly fast growers. The very next year, in spring or summer, you will need to pot on the plant or transplant it in open ground. A mature buddleja plant needs to be kept well-pruned and most varieties do best in a full-sun location.
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Here's How Horticulturists Propagate Ceanothus From Semi-Ripe Or Softwood Cuttings
IN THIS GUIDE Semi-Ripe Cuttings Softwood Cuttings Ceanothus is an attractive shrub and if you have one growing in your garden, you may well want more. These shrubs can be challenging to grow from seed, but the good news is that some ceanothus can be propagated relatively easily by means of cuttings. The method for taking cuttings depends on whether you are growing an evergreen or deciduous ceanothus. Evergreen ceanothus is best propagated by means of semi-ripe cuttings, taken between mid-summer and early autumn, whilst deciduous types are best propagated by softwood cuttings, taken in late spring. Both of these processes are relatively simple and ceanothus cuttings should create new flowering plants in around 2-3 years. I explain this relatively simple process in more detail below. Difficulty Easy to medium Equipment Required Gardening knife, secateurs, propagator When To Take Cuttings May to September Semi-Ripe Cuttings Between mid-summer and early autumn, select a healthy side shoot of current season growth from an evergreen ceanothus. Aim for around 10-15cm of growth. Peel the side shoot away from the main stem, leaving a small sliver of bark (known as a heel) attached. Dip the end of the cutting in a rooting compound for best results. Place the cutting in a heated propagator, in a container filled with a suitable potting mix, such as a blend of peat-free compost and perlite. A 1-litre pot is ideal and cuttings should be inserted to between a half and two-thirds their length. Grow on and continue to tend, watering when required, and cuttings should root well over the next growing season. Plant out well-rooted cuttings when the weather warms during the second spring. Softwood Cuttings Between late spring and midsummer, select a healthy, non-flowering stem tip of new growth from deciduous ceanothus. “For softwood cuttings, trim the bottom of the cutting to just below a node,” says Peter Lickorish, a Lecturer in Horticulture. Create a cutting around 10-15cm in length and then dip the cutting in a rooting hormone for best results. “Place it half to two-thirds deep in a finely crumbled peat-free compost,” Peter recommends. Keep the cuttings in a warm, humid environment for 4-6 weeks until they root. Once well-rooted, the cuttings can be potted on and later planted out into the garden. “Rotting and fungal problems are always concerns when taking cuttings,” Peter shares. “I find that pinching out the top bud and any tiny leaves at the top prevents these from rotting and the rot from spreading down the cutting. “Also, remove the lower half to two-thirds of the leaves on Ceanothus cuttings, by pinching them or trimming them delicately with a knife, to prevent these rotting when they touch the compost.”
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Ceanothus Leaves Turning Brown Or Yellow Are A Common Sign That Something Is Wrong
IN THIS GUIDE Brown Leaves 1) Frost Damage 2) Wind Burn 3) Water Issues Yellow Leaves 4) Over Or Under Watering 5) Nutrient Shortage Ceanothus can be relatively easy shrubs to grow. However, they can be rather picky about where they are grown and, if you place one of these shrubs in the wrong position or care for it incorrectly, there are a number of things that can go wrong. Leaves turning brown or yellow are common signs that something is wrong. Brown leaves are commonly a sign of: Frost damage Wind burn Water issues Yellow leaves can be a sign of: Waterlogged soil or water shortages Nutrient problems Read on to find out more about what might be causing this discolouration on your ceanothus leaves. Brown Leaves Brown leaves on a ceanothus plant are usually a sign that something is not right with the environmental conditions in which you are growing your plant. 1) Frost Damage Most commonly, brown leaves on a ceanothus are caused by frost damage. Ceanothus plants are somewhat hardy but can suffer damage during extreme winters or in colder and more exposed locations. Fortunately, a little frost damage can be removed and the plant should usually recover. 2) Wind Burn Brown leaves can also be caused by wind burn. It is important to grow ceanothus in as sheltered a position as possible, as winds can cause leaves to dry out more quickly than water can be replenished, causing them to brown and die back. 3) Water Issues Water shortage can be the reason for brown leaves, but it is important to work out whether that damage is caused by an actual lack of water availability or due to root damage, meaning that plants can’t take up the water they need. Root damage is frequently caused by waterlogged soil, which may also lead to a fungal infection. Ceanothus does need good drainage, so if your plant does not thrive, this is always one of the first things to look at. Yellow Leaves Yellow leaves on a ceanothus shrub are not always a cause for concern. Some leaves will naturally yellow and drop off as part of the natural life cycle of the plant. However, yellow leaves on a ceanothus shrub could also be a sign of an issue with water. ‘’While Ceanothus require watering while establishing, it’s crucial the soil drains well so the roots do not become waterlogged, and the application of a mulch of organic matter will improve the soil,” adds Master Horticulturist Roy Nicols. “Once established, Ceanothus does not require regular watering and only needs a good soak in drought conditions. “Overwatering is the most common mistake made when growing this plant.” 4) Over Or Under Watering Most commonly, yellow leaves are a sign of either overwatering or underwatering. Ceanothus are reasonably drought tolerant but can be rather fussy when it comes to their water needs. If you have yellow leaves, you might have watered too much or too little, or you might be growing your ceanothus in a spot that is not ideally suited to its growth. 5) Nutrient Shortage Yellow leaves can also be a sign of a nutrient problem. Leaves can become yellow or discoloured due to a nutrient deficiency in shallow, chalky soil. You may also have over-fertilised your plant. Of course, brown and yellow leaves can also indicate other problems such as pests or diseases. However, when looking for a cause, you should always look first at the environmental conditions to make sure the fundamentals are correct and that you are growing your ceanothus in the right place and the right way.
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Here's How To Plant And Grow Camellia Japonica - The RHS Award Winning Species
IN THIS GUIDE Overview Common Varieties Planting Camellia Japonica Care FAQs References Camellia japonica is a popular species of shrub with a range of interesting cultivars to choose from. Learn more about it, how to choose a variety and how to grow and care for it in this guide. These plants are beloved by gardeners, who prize their glossy evergreen foliage and their spring flowers. “I love fragrant plants that attract wildlife because I am very much a nature-friendly gardener,” shares Sue Fisher, an award-winning garden designer. “I have a Camellia shrub that is wonderful for pollinators and I love it.” Overview Botanical Name Camellia japonica Common Name(s) Common Camellia; Japanese Camellia Plant Type Shrub Native Area China, Japan and Korea Hardiness Rating H5 Foliage Evergreen Flowers Showy white or pink flowers When To Plant October to November When To Prune April to May Common camellia, also known as ‘Japanese Camellia’, is a species of flowering shrub in the Theaceae plant family. It is native to China, southern Korea and Japan, where it is known to grow in the wild in forests, specifically at altitudes between around 300-1100m.1 Although they are usually seen as smaller shrubs in gardens, in the wild they can grow into much larger shrubs or trees. “Camellias have such lovely flowers and colours, and they brighten up the dull days in the early part of the year,” says Lorraine Summers, Owner of Trehane Camellia and Blueberry Nursery. C. japonica The oldest C. japonicas in Europe are believed to have been planted in the 16th century after already being cultivated in Asia for hundreds of years before.2 Common Varieties “I always look for an RHS Award of Garden Merit if I have a choice to make between plants,” says Colin Skelly, a Horticulturist who has previous experience at The Eden Project. “It means that it has been trialled and found to perform reliably in gardens. “These plants can be considered tried and tested and a good bet if you’re making a planting decision.” Some of the notable cultivars of Camellia japonica that you can choose from that have received the RHS Award of Garden Merit are: C. japonica ‘Adelina Patti’ C. japonica ‘Alexander Hunter’ C. japonica ‘Ballet Dancer’ C. japonica ‘Bob Hope’ C. japonica ‘Drama Girl’ C. japonica ‘Gloire de Nantes’ C. japonica ‘Hagoromo’ C. japonica ‘Jupiter’ C. japonica ‘Lavinia Maggi’ C. japonica ‘Mars’ C. japonica ‘Nuccio’s Gem’ C. japonica ‘San Dimas’ C. japonica ‘Tricolor’ C. japonica ‘Tricolor’ Each of these would make an excellent starting point for growing in the UK’s climate.3 There are also numerous hybrids, such as C. japonica x williamsii, which have received an RHS Award of Garden Merit. Planting Japanese camellias are best planted out in the autumn, while the soil is still warm, so that they can establish strong root systems before the winter arrives. Most cultivars of C. japonica will do best if planted in an area with partial or dappled shade. Remember that these are relatively large shrubs, so you should allow at least 3-5m between these shrubs if you are planting more than one. Where To Grow Common Camellia C. japonica will work well in a low-maintenance garden as long as the environmental and soil conditions are appropriate. They will look great among other Asian species in a Japanese-style garden. They will also be at home in a traditional cottage garden, or in beds or borders in gardens of many other types. C. japonicas can also work well in city and courtyard gardens, and some cultivars are suitable for container cultivation. Sometimes, it is even grown as a houseplant indoors. Camellia Japonica Care Overwintering Common Camellia are hardy plants, with an RHS hardiness rating of H5. This means that they are hardy enough to make it through the coldest months in most places throughout the UK, even during severe winters. However, they should be placed in a sheltered spot, as they can be damaged by cold and drying winds. Buds and flowers may also be damaged by chilly temperatures and late frosts. Aspect Since C. japonica likes some shade, a south-facing spot may not be ideal. However, north, west and east-facing aspects can often work fine. One thing to note is that an east-facing spot where a camellia gets early morning sun is not ideal, because, in winter, this can cause the flower buds to dry out and thaw too quickly, increasing the chance of damage. Soil Requirements One of the most important things to remember when deciding where to grow C. japonicas is that these are ericaceous plants and will do best in acidic soil. If you have alkaline soil then it would be best to grow your camellias in containers filled with ericaceous peat-free compost or to choose plants better suited to the growing conditions that you can provide. The soil or growing medium should be moist but well-drained or well-drained. Watering Camellia japonicas should be watered regularly until they become established. “Camellias should be kept well-watered in August and September, as this can help to prevent bud drop in the spring,” Patricia explains. So, for the first year and a half or so, water regularly through the summer months, providing more water if the plants are grown in containers. Aim to keep the soil consistently moist at around 10cm below the surface. If in doubt, dig with a trowel to check if the soil is dry at this depth. When watering your garden, it is always best to use rainwater rather than tap water. If you have not already set up a rainwater harvesting system, make it a priority to do so right away. Watering with rainwater is especially important for camellias and other ericaceous plants if you live in a hard water area. Pruning & Training You can deadhead C. japonica when the flowers begin to fade to keep it looking fresh. However, this is not strictly necessary, as it is only for aesthetic reasons and will not have any impact on flowering the following year. Regular pruning is not needed for C. japonica, but if they grow larger than you want them to grow, you can give them a light trim after flowering has ended. If you wish to cut back harder to reduce the size of the shrub, this is best done in March, but note that hard pruning will mean that you will not have good flowering again for at least a couple of years. Feeding It can be beneficial to mulch around camellia plants with an ericaceous mulch each year in early spring. This will help retain moisture and will also provide slow-release fertility. You may also boost a plant that looks undernourished by feeding it with an organic fertiliser suitable for ericaceous plants in early spring. Be careful not to feed excessively and always stop feeding by the end of July at the latest. If you overdo the fertiliser or feed too late, this can lead to bud drop. Pot Growing C. japonica can be a good choice for container growing. Just remember that pots should be filled with an ericaceous medium that has a pH of between 5-6.5. Make sure that you choose a container a little larger than the existing root system of the plant. Common Pests & Problems Many of the common problems seen in C. japonica plants stem from a problem with environmental conditions or care. As long as you take note of all the above, place them in a suitable location and care for them correctly, they should be a relatively trouble-free plant. However, there are some problems that may arise, including: Fungal diseases (camellia gall, leaf or petal blight and root rot). Pests like vine weevil – which are more commonly seen on container-grown plants. Companion Planting Great companions for camellias are other plants which thrive in acidic soil conditions and in partial shade. In our interview, Patricia Short from the International Camellia Society suggested these companions for C. japonica: Roses Spring-flowering bulbs Cyclamen Digitalis I think that some other great choices are: Japanese maples Azaleas Rhododendrons Heathers Hellebores Heucheras Hostas Propagating C. japonica can be propagated by means of semi-ripe or hardwood cuttings, layering or grafting. FAQs How Big Does Camellia japonica Grow? C. japonica will grow into large shrubs and can ultimately be up to 10m tall and 8m wide. However, often they will remain somewhat smaller and growth can be restricted a little through light pruning if required. Fortunately, they are also pretty slow growing. If growing in pots, repotting will usually only be required every few years. Where Is The Best Place To Plant Camellias? In dappled or partial shade, in acidic soil, with a west-facing aspect. Does Common Camellia Make A Good Hedge? C. japonica can potentially be used to make a hedge in suitably shaded sot with acidic soil, but you will have to be very patient and dedicated since they grow slowly, and maintenance will take a lot of work. A different Camellia, C. sasanqua, is more commonly used to make hedges. This other plant has smaller leaves and a tighter habit of growth. References 1. Camellia japonica. (n.d.-b). NBN Atlas. Retrieved March 13, 2023, from https://species.nbnatlas.org/species/NBNSYS0500000250 2. Ancient camellias in Galicia and Portugal. (n.d.). International Camellia Society. Retrieved March 13, 2023, from https://internationalcamellia.org/en-us/articles/historical/ancient-camellias-in-galicia-and-portugal 3. AGM Plants July 2021. (n.d.). Royal Horticultural Society. Retrieved March 13, 2023, from https://www.rhs.org.uk/plants/pdfs/agm-lists/agm-ornamentals.pdf
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Feeding And Watering Guidelines For Camellia: 'Pine Wood Chip Is My Mulch Of Choice'
IN THIS GUIDE Watering Feeding Camellia can be relatively easy to care for, but things can go wrong, so it is important to carefully consider where you grow and how you tend to it to avoid the most common pitfalls. Some of the mistakes often made when growing camellias revolve around watering and feeding. Getting these two things right is crucial for growing healthy and happy plants, as I explain below. Watering When watering camellias, you need to remember that they like free-draining conditions. Do not overwater and always make sure that excess water can drain away freely. Another key thing to bear in mind is that you want to keep the conditions acidic, as camellias prefer a pH somewhere between 5-6.5. For this reason, you should water with rainwater wherever possible, especially if you have hard water where you live, as tap water can be far too alkaline in some areas. Camellias will typically need to be watered more frequently when grown in containers than when grown in the ground. You should water deeply whenever the top few centimetres of the growing medium feels dry. Plants growing in the ground will also need to be watered well during the period of establishment, especially for the first 18 months or so and during particularly dry spells in summer. “Camellias should be kept well-watered in August and September, as this can help to prevent bud drop in the spring”, explains Patricia Short from the International Camellia Society. Well-established and larger shrubs will typically require less watering and care in general. When watering, it is important to try to water the soil below the plants and not the plants themselves. This not only ensures that water gets to where it is needed but also helps to reduce the chances of a fungal infection. A mulch on top of the soil can also help prevent fungal spores from being splashed up onto the leaves. Feeding In the early spring, feed your camellias with an ericaceous organic fertiliser and add a mulch around your plants. A mulch of pine needles, coniferous bark or other similar materials can be ideal. “Feed the soil, not the plant, is a good adage to follow,” says Master Horticulturist Colin Skelly. “The mulch breaks down feeding the Camellia slowly over time, whilst also increasing moisture and reducing evaporation. “Remember to use an acidifying mulch: pine wood chip mulch is my ericaceous mulch of choice.” You can also consider using an organic liquid plant feed, though this is usually only required when growing camellias in containers. Less is more when it comes to fertilising camellias and it is more important to ensure a fertile growing medium than to feed additionally through the growing season. To maintain fertility in the growing medium, make sure you top dress the containers and repot into a new growing medium every 2-3 years. When using an organic liquid fertiliser, it is important not to overdo it, making sure that you always stop fertilising a camellia before the end of July. Feeding later in summer and into autumn can cause buds to drop from the plant the following year.
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Acidic Soil Is A Must For Camellia Plants - And Do Everything To Avoid Waterlogging
IN THIS GUIDE Preferred Soil Type Soil Moisture Potting Mix Camellia can be a relatively low-maintenance option for the garden, but it can quickly become far more work and less reliable if you do not grow it in an appropriate position. Camellias can be grown in pots or in the ground if the soil is suitable. However, it is vital to provide the right conditions when it comes to the soil or growing medium where you wish to grow these shrubs. Here are the basic things you need to know before growing: Camellias can be grown in clay, loam or sand in a garden. They absolutely must have acidic soil conditions. They cannot tolerate waterlogging. When a suitable site is not available in the soil in a garden, camellia can be grown (in ericaceous compost) in pots. Preferred Soil Type The first thing to look at if you would like to grow camellias in your garden soil is the soil type you have in your garden. Camellias will typically thrive in clay, loam or sand. Any of these above soil types, as long as it is relatively fertile, should be suitable for these shrubs. After you have determined your soil type, it is vital to look at one characteristic of the soil in particular – pH. Above all else, when it comes to choosing a site and looking at your soil, it is important to understand that these plants need an acidic to neutral soil – ideally with a pH between 5.5-6.5. Soil Moisture Another important characteristic to look at when determining whether your garden soil is appropriate for growing camellias is moisture retention and the potential for waterlogging. Camellias are actually fairly resilient and can cope with a lot. However, one thing that they cannot usually cope with at all is damp, boggy soil. “If you aren’t sure about you garden conditions yet then wait until you are before choosing to plant,” Horticulturist Colin Skelly recommends. “Take some pH tests across the garden to give you an idea of the general acidity and of any differences across the site. “Then, in the middle of winter after some wet weather, observe the ground conditions in the garden. “Ask yourself where does the water pool? Do any spots drain more freely than others? In summer, do the same. Where is the soil still moist? Where is it drier? “Camellias will suit a spot that is not boggy in winter but still relatively moist in summer.” Fortunately, even if you have a heavier clay soil that is prone to waterlogging, you can add plenty of organic matter to improve drainage. Potting Mix If you don’t have acidic and moist yet free-draining soil in your garden, some amendment might be possible, but instead it might be better to grow them in containers. If you are growing a camellia in a container, make sure that you choose a suitable peat-free ericaceous compost. Repot with fresh medium every 2-3 years to maintain the appropriate fertility and pH level and to make sure compaction does not occur.
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'Crimson King' And 'Ruby Wedding' - A Selection Of 19 Remarkable Red Camellias
IN THIS GUIDE 1) C. japonica ‘Alexander Hunter’ 2) C. japonica ‘Adolphe Audusson’ 3) C. ‘Black Lace’ 4) C. japonica ‘Black Prince’ 5) C. japonica ‘Bob Hope’ 6) C. japonica ‘Bob’s Tinsie’ 7) C. japonica ‘Coquettii’ 8) C. japonica ‘Grand Prix’ 9) C. japonica ‘Grand Slam’ 10) C. japonica ‘Jupiter’ 11) C. japonica ‘Kramer’s Supreme’ 12) C. japonica ‘Mars’ 13) C. japonica ‘Mercury’ 14) C. ‘Tom Knudsen’ 15) C. ‘Royalty’ 16) C. sasanqua ‘Crimson King’ 17) C. × williamsii ‘Freedom Bell’ 18) C. × williamsii ‘Les Jury’ 19) C. × williamsii ‘Ruby Wedding’ There are a huge variety of different camellia shrubs to choose from, with flowers coming in a range of hues. One way to start narrowing down your choices is to look at the colour of the blooms. With large dramatic flowers, red camellias can be wonderful for bringing a vibrant and exotic feel to your garden. All of these options are H5 hardy and can be grown in most soil types with an acidic pH as long as they are sited in a sheltered position. 1) C. japonica ‘Alexander Hunter’ COMMON NAME(S): camellia ‘alexander hunter’ FLOWERING SEASON(S): spring SUNLIGHT: full / part shade SIZE: 2.5-4m in height, 2.5-4m spread This large shrub with a compact growth habit and upright form can grow up to around 2-4m in height and width. Its flowers are deep crimson in colour, with single or double forms, and grow to around 10cm across. This plant is H5 hardy. 2) C. japonica ‘Adolphe Audusson’ COMMON NAME(S): camellia ‘adolphe audusson’ FLOWERING SEASON(S): spring SUNLIGHT: full / part shade SIZE: 1-1.5m in height, 1-1.5m spread Growing quite large where conditions are ideal, this camellia has a fairly compact habit of growth. Its flowers are semi-double and are a rich red in hue with yellow stamens, and can grow to around 10-12cm in diameter. This plant is H5 hardy. 3) C. ‘Black Lace’ COMMON NAME(S): camellia ‘black lace’ FLOWERING SEASON(S): spring SUNLIGHT: full / part shade SIZE: 1.5-2.5m in height, 1.5-2.5m spread A compact camellia rarely exceeding 2.5m in size, this option is one for those who love order, symmetry and precision in blooms, as Master Horticulturist Colin Skelly shares: “I love the geometry of C. ‘Black Lace’, which contrasts with single flowered species and cultivars. “I never fail to be awe-struck by the beautiful patterns of plant and flower forms. “The only downside of these and similar double forms is that the pollen and nectar are difficult for pollinators to access.” The geometric flowers are a deep red and form dramatic and orderly patterns against the deep green leaves. This plant is also H5 hardy. 4) C. japonica ‘Black Prince’ COMMON NAME(S): camellia ‘konronkoku’ FLOWERING SEASON(S): spring SUNLIGHT: full / part shade SIZE: 1.5-2.5m in height, 1.5-2.5m spread Also known by the name ‘Konronkoku’, this camellia cultivar has beautiful, rich, red, double flowers that are around 10cm across, which bloom in later spring. The shrub remains compact and grows to around 2.5m in height and width. 5) C. japonica ‘Bob Hope’ COMMON NAME(S): camellia ‘bob hope’ FLOWERING SEASON(S): spring SUNLIGHT: full / part shade SIZE: 2.5-4m in height, 1.5-2.5m spread Growing to around 3m, this camellia is another great option. It has deep red, semi-double flowers which can grow to around 12cm across. These lovely flowers bloom in the spring. 6) C. japonica ‘Bob’s Tinsie’ COMMON NAME(S): camellia ‘bob’s tinsie’ FLOWERING SEASON(S): spring SUNLIGHT: full / part shade SIZE: 1.5-2.5m in height, 0.5-1m spread A great option for smaller spaces or a container, this camellia grows to around 2.5m tall and 1m wide. It is notable for its anemone-form and double flowers with a bright red hue, which open to around 8cm across. 7) C. japonica ‘Coquettii’ COMMON NAME(S): camellia ‘coquettii’ FLOWERING SEASON(S): spring SUNLIGHT: full / part shade SIZE: 1.5-2.5m in height, 1.5-2.5m spread With light, bright red, double flowers around 10cm across, this is another stunner. It is medium-sized and quite slow growing, reaching around 2.5m in height and width if grown in optimal conditions and allowed to do so. 8) C. japonica ‘Grand Prix’ COMMON NAME(S): camellia ‘grand prix’ FLOWERING SEASON(S): spring SUNLIGHT: full / part shade SIZE: 4-8m in height, 4-8m spread A vigorous and medium-sized shrub that grows between 4-8m wide and tall, this camellia has bright red semi-double blooms which can be around 13cm in diameter. This cultivar is H5 hardy. 9) C. japonica ‘Grand Slam’ COMMON NAME(S): camellia ‘grand slam’ FLOWERING SEASON(S): spring SUNLIGHT: full / part shade SIZE: 2.5-4m in height, 2.5-4m spread Growing to around 4m in height, this camellia has dark, glossy leaves and anemone-form double or semi-double blooms with a deep red hue that open to around 12cm across. This variety is also H5 hardy. 10) C. japonica ‘Jupiter’ COMMON NAME(S): camellia ‘jupiter’ FLOWERING SEASON(S): spring SUNLIGHT: full / part shade SIZE: 2.5-4m in height, 1.5-2.5m spread Up to around 4m tall and 2.5m wide, this vigorous evergreen shrub has single or semi-double, rose-red, bowl-shaped blooms that are 9cm in diameter and have prominent golden stamens at the centre that are occasionally blotched with white. 11) C. japonica ‘Kramer’s Supreme’ COMMON NAME(S): camellia ‘kramer’s supreme’ FLOWERING SEASON(S): spring SUNLIGHT: full / part shade SIZE: 2.5-4m in height, 1.5-2.5m spread This lovely, large evergreen shrub grows with an upright and bushy form to around 4m tall and 2.5m wide. It has dark, glossy green leaves and, in the late winter to early spring, boasts large, double, peony-form flowers with good fragrance. 12) C. japonica ‘Mars’ COMMON NAME(S): camellia ‘mars’ FLOWERING SEASON(S): spring SUNLIGHT: full / part shade SIZE: 2.5-4m in height, 2.5-4m spread This large shrub with a lax habit can grow around 4m in height and width. The flowers on this camellia variety grow to around 12cm across and are deep red with prominent goldeny-yellow stamens. 13) C. japonica ‘Mercury’ COMMON NAME(S): camellia ‘mercury’ FLOWERING SEASON(S): spring SUNLIGHT: full / part shade SIZE: 1.5-2.5m in height, 1.5-2.5m spread Around 2.5m tall and wide at maturity, this compact camellia has crimson double blooms which are around 12cm across. These bloom in mid to late spring and are H5 hardy. 14) C. ‘Tom Knudsen’ COMMON NAME(S): camellia ‘tom Knudsen’ FLOWERING SEASON(S): winter / spring SUNLIGHT: full / part shade SIZE: 1.5-2.5m in height, 1.5-2.5m spread Also growing up to around 2.5m tall and wide, this is a compact hybrid camellia and is a cross between C. japonica and C. reticulata. It has deep rich green foliage and the flowers, which are of peony form, are double and deep red, blooming in winter and early spring. This cultivar is H4 hardy. 15) C. ‘Royalty’ COMMON NAME(S): camellia ‘royalty’ FLOWERING SEASON(S): spring SUNLIGHT: full / part shade SIZE: 0.5-1m in height, 0.5-1m spread This small and compact camellia rarely exceeds 1m in height and width. It has a lax growth habit, glossy dark green leaves and very large light red, semi-double flowers which are borne in mid or late spring. 16) C. sasanqua ‘Crimson King’ COMMON NAME(S): camellia ‘crimson king’ FLOWERING SEASON(S): autumn / winter SUNLIGHT: full shade / full sun / part shade SIZE: 1.5-2.5m in height, 1.5-2.5m spread Growing around 2.5m in height and width, this camellia is another great evergreen shrub for many gardens. One notable thing about this type of camellia is that it can cope in full sun as well as in shade. The light red flowers are single and fragrant, with yellow stamens at the centre. This variety is H4 hardy. 17) C. × williamsii ‘Freedom Bell’ COMMON NAME(S): camellia ‘freedom bell’ FLOWERING SEASON(S): winter / spring SUNLIGHT: full / part shade SIZE: 1.5-2.5m in height, 1.5-2.5m spread The bright red flowers on this evergreen shrub bloom from late winter. They are funnel-shaped and semi-double, and look beautiful against the deep green foliage. Another camellia variety that is H5 hardy. 18) C. × williamsii ‘Les Jury’ COMMON NAME(S): camellia ‘les jury’ FLOWERING SEASON(S): spring SUNLIGHT: full / part shade SIZE: 1.5-2.5m in height, 1-1.5m spread This camellia grows to around 2.5m tall and 1.5m wide. It flowers in early to mid spring, producing formal double blooms with a vibrant crimson hue. This variety is also H5 hardy. 19) C. × williamsii ‘Ruby Wedding’ COMMON NAME(S): camellia ‘ruby wedding’ FLOWERING SEASON(S): spring SUNLIGHT: full / part shade SIZE: 1.5-2.5m in height, 1-1.5m spread Growing to around 1.8m tall and wide, this popular camellia variety has glossy, dark green foliage and bright red flowers. The blooms are double and are anemone to peony-form.
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Sowing Camellia Seeds Requires Lots Of Patience - Here's 6 Steps If You Want To Give It A Go
IN THIS GUIDE 1) Collect Seed Pods 2) Soak Seeds Overnight 3) Sow Camellia Seeds 4) Wait For Germination 5) Trim The Taproot 6) Patiently Wait For Flowering Camellias are not the easiest plant to grow from seed, mainly due to the fact that this is a process that requires a great deal of patience. If you want to propagate new plants for your garden that look like the parent plant, you are best propagating these shrubs by taking either semi-ripe or hardwood cuttings. You can also try layering or grafting if you are a more experienced horticulturalist. However, should you wish to experiment with growing your own camellias from seed, here is the process to follow: Collect the seeds from an existing camellia. Soak the seeds overnight to increase the chances of success. Sow your camellia seeds in a seed tray or container, covering them with a light layer of compost. Water them in, then wait for germination to take place (this step requires patience as it can take months). Cut any long taproot to encourage bushier roots. Wait for your camellia seedlings to finish growing. We explore each step below. Difficulty Medium Equipment Required Seeds, seed tray, seed-starting compost When To Sow Spring or autumn 1) Collect Seed Pods The first part of the process is to collect seeds from an existing camellia. “The seed will be the result of two parents and therefore a mixture of the characteristics of both of them,” explains Master Horticulturist Colin Skelly. “Therefore, your new camellia will be a unique seedling. The chances of it being a show stopper are not high, as professionals regularly scan thousands of new deliberately crossed seedlings for new introductions. “However, having your own seedling has a charm of its own.” It may be necessary to tie a bag around a stem to collect these, though you may be able to collect them from the ground around an existing shrub. These are weighty seeds and shouldn’t be too difficult to recognise. 2) Soak Seeds Overnight The seeds that are collected should be sown as soon as possible. Many gardeners find that there is a better chance of successful germination if the seeds are soaked overnight in tepid water to break down the coating around the seeds before they are sown. 3) Sow Camellia Seeds Choose a seed tray, pot or another container, fill these with a seed starting potting mix and sow your camellia seeds. Press your camellia seeds into the surface of the compost with the eye facing downwards or to the side. Afterwards, cover them over lightly with the compost mix and water them in, allowing excess water to drain away. 4) Wait For Germination Be patient, as camellia seeds can take several months to germinate and will likely do so the following spring. Take good care of them over the winter months. 5) Trim The Taproot Once the seedling has developed shoots above the surface of the growing medium, it is a good idea to cut the long taproot that grows straight down to encourage bushier roots. This will also make sure that the plant remains as comfortable as possible in its container. Pot on your young camellia when required as it grows. 6) Patiently Wait For Flowering Remember, it will take around 5-7 years before your camellias will begin to flower, and when they do, they may not flower in the same way as their parent plant. So, you will need to wait a long time to see the results and discover whether your efforts were worthwhile.
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