Reviewed By COLIN SKELLY
Colin is a Horticulturist and Horticultural Consultant with experience in a range of practical and managerial roles across heritage, commercial and public horticulture. He holds the Royal Horticultural Society’s Master of Horticulture award and has a particular interest in horticultural ecology and naturalistic planting for habitat and climate resilience.
Contributions From SALLY FLATMAN
Sally Flatman is the host and creator of the 'Our Plant Stories' podcast. She is a former BBC Radio producer and has received an RHS Level 2 Certificate in the Principles of Horticulture from Capel Manor College.
IN THIS GUIDE
One genus, a dazzling array of varieties – and so much so that to the untrained eye, Aquilegia species, hybrids and cultivars may be mistaken for entirely different, unrelated flowers.
Also called columbine, most varieties display distinctive spurs but what really distinguishes this wildflower is its nearly infinite colour gamut and its blend of exotic yet delicate charm.
‘I’ve always loved plants like Aquilegia because they are very forgiving,” shares Gardener Sally Flatman.
“Even in a shaded garden, they grow and spread.”
The columbine is but a common wildflower that has made itself multiple recipients of the Royal Horticultural Society’s Award of Garden Merit.
It is a herbaceous perennial that is self-seeding and – to its greater merit – ‘self-hybridising’.
This is because it cross-pollinates and inter-breeds. So if you end up growing these lovely plants, consider not deadheading them all, instead letting them go to seed – and then take pleasure in the new strains, shapes, and hues that adorn your garden the following year!
“If you grown the common Columbine species, Aquilegia vulgaris, then it will self-seed readily around your garden, finding the most favourable spots,” shares Colin Skelly, a Master Horticulturist.
“If your neighbour has a cultivated form or if you choose different species or cultivars, they will hybridise readily and produce seedlings unique to your garden.
“If there is one you really like you can propagate it by division as the seed won’t be true to the parent plant.”
Overview
| Botanical Name | Aquilegia |
| Common Name(s) | Granny’s Bonnet, Columbine |
| Plant Type | Perennial Flower |
| Native Area | Various |
| Hardiness Rating | H5 |
| Foliage | Herbaceous, pale green leaves |
| Flowers | Varied flowers |
| When To Sow | March, April, May |
| Flowering Months | May, June |
| When To Prune | June, October, November |
Sunlight
Preferred
Full Sun / Partial Shade
Exposure
Exposed or Sheltered
Size
Height
0.1 – 0.5M
Spread
0.1 – 0.5M
Bloom Time
May – June
Soil
Preferred
Loam, Sand
Moisture
Moist but well drained
pH
Any
Variously described as ‘beautiful’ and ‘stunning,’ yet also as a ‘shy’ ‘cottage garden’ denizen, the columbine is self-evidently many things to many people.
The larger species sprawl out to 75cm or more in diameter and grow to be as tall; Aquilegia vulgaris or the common columbine reaches a full metre in height.
However, dwarf cultivars are petite and are ideal for compact spaces.
Aquilegia vulgaris ‘Nana’ grows to only 25cm and Aquilegia buergeriana ‘Calimero’ not even to 20cm.
Notwithstanding such diversity, for the most part the flowers have five sepals and five petals, and even five pistils.
Aquilegia flowers are not only visual delights for you and I; they are magnets for honey-bees, bumble-bees, butterflies, and hummingbirds.
Hence, a bed or two of columbine will add an extra layer of nature’s beauty to your garden.
With about 130 species and many more hybridised cultivars to choose from – and with such a profusion of floral ‘styles’ at that – you’ll be spoilt for choice.1Aquilegia. (n.d.). Kew Royal Botanic Gardens. Retrieved April 11, 2023, from https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:325954-2#children
Belying its delicate and exotic blooms, columbines are one of the plant world’s good sports; these low-maintenance charmers get by on the most basic care and are not particularly picky about soil and growing conditions.
This quality makes them especially suitable for casual gardeners with limited time.
Here are camera angles of a beautiful Aquilegia variety I grew from seed in an outdoor planter earlier this year:
You may notice how the flower stems rise high above the unfurling foliage (which is beautiful in its own right) and the highly unusual shape of the flower heads.
Habitat & Growing Conditions
Woodlands, riversides, hillsides, and meadows in the temperate and cool regions of the Northern Hemisphere are the favoured habitats of Aquilegia.2Columbine. (n.d.). Plant Atlas. Retrieved March 9, 2023, from https://plantatlas2020.org/atlas/2cd4p9h.yc6
The plants are further inclined to dappled sun, as on the rim of a woods, or partial shade, as near the base of a rocky outcropping.
While some Aquilegia fare well in dry soil, the greater part thrive in moist, well-drained soils.
Columbine season is from late spring to early summer, between the early spring bulbs and the summer flowering season.
Aquilegia Plant Care
Aquilegia are remarkably unfussy and sporting plants, with most varieties making do with whatever they get.
However, to get the best out of your plants, tailor the growing conditions to their liking.
Preferred Soil
I find that these plants prefer rich soil; humus or loam mixed with sand or chalk is best but dense clay is to be avoided.
The soil should not be allowed to dry out and should be kept moist but it must drain well.
The ideal pH range is 6.0 to 7.0 though a ±1 swing will be perfectly acceptable to your columbine.
Watering & Feeding
In temperate zones twice-weekly watering is sufficient when grown in pots, but in warm climates or during hot weather more frequent watering may be necessary.
Most varieties do well without any fertiliser; that said, feeding your plant with water-soluble 5-10-5 fertiliser will result in lusher foliage and brighter, healthier blooms, particularly for pot-grown plants.
Sunlight
Though most columbines do just fine in full sun, most do even better in dappled sun or partial shade.
Plant them close to taller plants in sunny climes to provide shade for at least part of the day.
In the UK these plants are H7 hardy, meaning they are fully resilient against frost and freezing across the British Isles.3Aquilegia vulgaris. (n.d.). Royal Horticultural Society. Retrieved March 9, 2023, from https://www.rhs.org.uk/plants/100859/i-aquilegia-vulgaris-i/details
Pruning
For many plants, pruning is a ‘best practices’ requirement but for Aquilegia it is more of an optional, strategic decision.
On an ongoing basis, you can pinch off dead flowers or snip them where the flower stalk meets the stem.
Soon after the initial bloom cycle you can cut the stems to their respective halfway points and trim some of the foliage.
Not only will this improve the plants’ appearance, but it may also induce a welcome second round of blooms in early summer.
After any second bloom or before the end of summer, say in July, prune the plant down to its basal leaves; these are the larger leaves that issue from the main stem just above the soil.
This pruning will redirect nutrients to the roots instead of to unproductive stems, thereby building resources for the following year.
Deadheading
When the initial flowering cycle ends, you can deadhead by cutting off the stems to the basal leaves.
The first reason is to prevent inter-pollinated self-seeding, should you so wish, by this happily inter-fertile genus – if you would rather have established species and cultivars in your garden instead of random and unpredictable new strains, then you would deadhead.
The second reason is to enhance plant vitality as it will result in bigger blooms the following year, and also to increase its productive lifespan as plant resources will not be spent on producing seeds.
Deadheading is a special form of pruning, having to do with prompt removal of spent blooms.
If you want to deadhead, cut terminal flowers about 1cm above the leaves below it.
Cut lateral flowers where their stalk joins the main stem if the main stem has blooms further up the main stem, but if not then cut off the main stem itself at a point just below where the spent bloom’s stalk joins it.
A happy compromise might be to deadhead somewhat more than 50% of the flowers after the second or last bloom cycle while letting the rest go to seed.
Because columbines tend to wither and die in about four years, you may wish to take advantage of its propensity to self-seed.
Division
Remember that if you already have Aquilegia then you can ‘buy’ this plant from home by division (or separation).
It is not easy but quite possible:
- Choose a big, spread-out clump in early spring and dig very deeply in a circle all around the roots.
- Pull up the plant with the soil around the roots, divide the roots with a clean sharp knife, leaving as much soil as you can around the roots, and replant promptly.
- Apply a mulch of compost around the divided plants.
Note that divided Aquilegia may take some time to gain vitality.
You can divide an Aquilegia plant every other year.
Common Problems
This generally healthy and trouble-free plant has but two ‘enemies’: powdery mildew and leaf miners.
Powdery Mildew
Powdery mildew attacks columbine when it is wet and rainy or when you have warm days and cool nights.
To combat it, cut off the affected parts of the plant, doing so to a couple of centimetres from soil level if need be.
Give the plant plenty of sun and ample air circulation to help it avoid another bout of powdery mildew.
Leaf Miners
If you see a leaf miner infestation, you can wait until the blooms are spent before cutting down and destroying affected parts of the plant or you may do so immediately.
FAQ’s
When Do Aquilegias Flower?
As any number of sites parrot, Aquilegias flower after the early spring bulbs and before the peak flowering season. Basically, this means May.
However, I generally find that if conditions are warm enough, some Aquilegias may flower in late April.
If you prune your plants then they may well flower again in the summer.
Keep in mind that if you grow Aquilegias from seeds, they will flower on their second year.
What Should I Do With Aquilegias After Flowering?
It depends on what your intentions are.
If you wish to preserve the vitality and increase the lifespan of the plant or if you do not want your Aquilegias to self-seed after cross-pollination and, thereby, grow new and unpredictable hybrids, then you should deadhead the plant.
Otherwise, if you would like to see new and unexpected strains of Aguilegia decorating your garden the following year, do not deadhead or deadhead about 50% of the spent blooms.
See preceding section Deadheading Aquilegia for details.
Will The Plant Flower Twice?
It very well may if you prune the plant – but no guarantees!
The trick in making columbine flower again that same season is to give it a good ‘haircut’ after the initial flowering cycle.
See preceding section Pruning Aquilegia for details.
What Are The Best Plants To Grow With Aquilegias?
You may have seen this question ‘answered’ on many a site but it is a red herring of a question and the answers, therefore, are of little value.
The reason is that Aquilegia is so exceptionally varied a genus (refer to the earlier sub-head Infinite Variety) that plants may go very well with and complement a particular species, hybrid, or cultivar of columbine while it may equally well look out of place, clash, or compete, with another species, hybrid, or cultivar.
The valid question would run along the lines of “What are the best plants to grow with ‘Black Barlow’ and similar varieties?”
You will at once realise that plants that would go well with, set off, or complement ‘Black Barlow’ may well not work alongside Aquilegia formosa or ‘Blue Star’.
