Dianthus Feeding And Watering Guidelines: Make Sure To Facilitate Very Good Drainage
Reviewed By ROY NICOL
Roy is a Professional Gardener and Horticultural Consultant, specialising in large garden year-round maintenance and garden development. He is an RHS Master of Horticulture and uses his research in the application of no-dig methods in ornamental garden settings. Roy has been a Professional Gardener for more than six years and is a member of the Chartered Institute of Horticulture, Professional Gardener's Guild and Association of Professional Landscapers (Professional Gardener).
Contributions From EMILY CUPIT
Emily is a Gardening Writer, Photographer and Videographer from Derbyshire, UK. She is the Founder of Emily's Green Diary - a community of more than 75,000 people who share in her gardening journey.
Dianthus, the Flower of the Greek god Zeus, is, in fact, the name of a genus that includes three super-popular flowering plants: Carnations, Pinks, and Sweet Williams.
Dianthus, as a genus, is a little too often typecast and sometimes mischaracterised as being suited best for cottage gardens.
To correct the record, though Sweet Williams may well be cottage garden mainstays, we submit that carnations are ‘courtyard garden classics’.
Carnation flowers with their pastel, genteel shades, refined looks, and subtle charms are well-suited for formal gardens as well, with that restrained, conservative glaucous foliage putting the final touches on the ‘formal’ dress code.
Whether it’s ruffled carnations, fringed pinks or dainty Sweet Williams that are most to your taste, you will get the best out of your plants if you follow these watering and feeding guidelines.
Watering
Where watering Dianthus is concerned, one had better start with soil and drainage.
All types of Dianthus are quite susceptible to root rot, crown rot, and stem rot (yes, all three) so soil must drain very well.
To facilitate very good drainage – besides other factors – soil should not be heavy or clayey; at the same time, be mindful that Dianthus need a soil pH level from neutral to slightly alkaline.
Be sure that containers and pots have drainage holes.
As a general rule, assuming there is no rain and you’re enjoying ‘normal’ weather, give open-ground Dianthus an inch of water per week.
In hot weather water them twice a week.
Do not keep the soil consistently moist – let the soil just dry out between waterings.
This is especially important in the winter when you should also decrease the amount and frequency of watering.
To water by feel, allow the soil to dry out to a depth of 3-4cm before watering again.
In hot weather do monitor soil moisture levels and especially so for containerised Dianthus plants.
If the container’s soil does not include moisture-retentive media, it will dry out very soon in high heat.
It would be well to water at soil level though this is not so critical for Dianthus as for some other plants.
However, virtually all flowering plants are best watered by mid-morning.
Feeding
Though Dianthus are not heavy feeders and perform perfectly well without fertilising, they do require rich, fertile soil – that is a ‘non-negotiable’.
When planting Dianthus of any kind, fork over the soil to a depth of about 25cm and amend with a generous quantity of organic compost or humus – that will do for ‘fertiliser’.
You may amend the soil with well-rotted manure too but do not use chicken manure for Dianthus as this will just encourage leafy growth rather than flowers.
(And while you’re amending the soil, you could also look into drainage, and add grit, sand, or perlite, as appropriate.)
Feeding Dianthus is an ‘extra’ and if you can do it, all the better, as this will encourage more flowering throughout the season.
What with the thousands of cultivars of carnations, pinks, and Sweet Williams, different groupings have slightly different ‘feeding preferences,’ so to speak.
That said, you can’t go wrong feeding any Dianthus by either:
- Applying once in early spring and again in late summer a controlled-release or slow-release balanced fertiliser like Miracle-Gro Shake ’n’ Feed All Purpose Continuous Release or Osmocote Controlled Release Plant Food, or,
- Feeding every few weeks with a balanced liquid fertiliser like Miracle-Gro All Purpose or a special-purpose formula such as Grow-More’s 3-6-6 Flower and Bloom.
We suggest that for Dianthus you apply fertiliser at 70-80% of the proportion or quantity indicated in the manufacturer’s directions.
