6 Frost-Tolerant Flowers for May in Zones 6–7
As a flower farmer, ensuring that I have flowers in multiple seasons is important. If you’re a hobby gardener or flower farmer, in this article you’ll find six frost-tolerant flowers that do well for cut flower work (five perennials and one vigorous self-seeding annual).
Frost Tolerant Perennials that Saved the Day
Following a very heavy mid-May frost and tricky dry spring conditions, these six stalwarts were the stopgap between the tulips and the overwintered annuals, alliums, and iris.
Without these frost-tolerant flowers, I would have been very short of flowers to cut indeed, and I intend to propagate more of them for use next season.
They were particularly valuable to me this year because we had such a hot, dry spring (quite out of character for Cumbria), which meant the tulips were over very quickly, and I hadn’t planted enough alliums to take over. Also, I had no ranunculus and anemones due to a vole attack over winter!
1. Perennial Cornflower (Centaurea Montana)
Perennial cornflower are hardy perennials have a good vase life and come in several colours. For the longest vase life, harvest these flowers when in bud with the petal colour showing.
Blue is the most readily available variety,
Very dark purple, varieties such as “Jordy,” and “Black Sprite”
Mauve, C. “Lilac”
White, C. “Alba”
White with a purple centre, varieties such as “Purple Heart.”
2. pale pink bistort, Persicaria Bistorta “Superba” or “Superbum”
Next up is this beautiful little flower. Pick bistort when the pink bottle brushes start to fluff out at the base but the florets are still closed at the tips.
3. Aquilegia (also known as Columbine)
This flower is a perennial and has flowers that come in various shapes, sizes, and colours. Flowers can be double or single, some with elegant long spurs at the back of the flower.
Aquilegia (columbine) has several flowers to a stem, so pick when the first flower is open, and the rest should follow. It is a plant easily raised from seed. However, when it self seeds, it will cross-pollinate and rarely comes true to form. This can lead to some good surprises; however—in my experience—after a few years of self-seeding, a lot of them are the same pink.
Here are some popular varieties:
A. Chysantha has large pale golden flowers
A. Clematiflora “Green Apples” has layers of white petals tinged with green
A. Coerulea “McKana Giant Hybrids” produces large flowers up to 4 inches long in a range of white, yellow, crimson, and blues.
A. Hybrida “Songbird Series” also provides large flowers in bicolours, such as “Robin” (pinks and single colours) and “Dove,” which is white.
A. Viridiflora “Chocolate Soldier” has very unusual purply brown flowers with green sepals and is also scented.
The “Barlow” types come in many colours and are very frilly, with double petals forming tight little bells.
4. Hosta
A perfect perennial for foliage in May is the hosta. They may take a few years to bulk up into a good clump, but they are a great addition.
Hostas come in many shades of green (some variegated white or yellow) and have leaves of varying sizes. The leaves also last well out of water for buttonholes, boutonnieres, flower crowns, etc. There are hundreds of varieties to choose from, most will also flower later in the year, and some of them even have scented flowers.
5. Hesperis Matronalis (Sweet Rocket or Dame’s Rocket)
This short-lived frost-tolerant perennial flower is often grown as a biennial. The flowers are sweetly scented and can be white, sometimes tinged with pink, or a bright purple.
6. Don’t Forget the Forget-Me-Not
One more useful plant during May is the forget-me-not (Myosotis). Although not a perennial, it self-seeds happily, so once you have it, you will probably never need to worry about not having it ever again!
