Cool Flowers:
Sowing and harvesting hardy annuals
When I started sowing annuals, I made an interesting discovery: many varieties self-seeded, and some of them bloomed much earlier and more profusely the following year than the usual summer flowers. A sea of nigellas was already in bloom by May, while my spring-sown ones still weren't really getting going at the end of June. What was their secret?
These were so-called “Cool Flowers” – Hardy annuals that were unaffected by frost and cold. On the contrary: some even needed the cold for germination.
While zinnias and cosmos must only be planted out in frost-free soil, Nigellas (Maiden in a Green), poppy seeds, annual larkspurs and many others are truly "winter-hardy." And if you learn to utilize this characteristic, your cut flower garden will be beautifully in full bloom from late spring onwards. But even without a dedicated cut flower garden, cool flowers fill an important gap between bulbous plants and the actual summer flowers – a time when most gardens tend to be rather dreary.
How do you sow Cool Flowers?
The best way is to sow the seeds outdoors in small pots in a rain-protected spot as soon as autumn arrives, and later transplant the seedlings into the garden bed. If you missed sowing in autumn, you can also start at the end of February/March. In colder regions, it's best to start indoors (in a cool but bright location!) and then plant them directly outdoors from the end of March/April onwards, once the soil has warmed up a bit. Germination can actually be accelerated by placing the seeds in the refrigerator for a week before sowing.
Those who desire an endless abundance of flowers should plan two further subsequent sowings: one together with the cold-sensitive annuals (planting out from May 15th) and another in early summer (sowing at the end of April/planting out in June).
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Certain varieties are often sown directly into the garden bed: poppies, nigellas, and the annual delphinium are among them. However, the soil should be prepared and weed-free, and the seedlings must not be confused with weeds later on.
I like to sprinkle a little poppy into the perennial beds in September; it provides fullness and color when only the leaves of the perennials are visible in early summer.
Last year I sowed Cool Flowers in containers for the first time and was thrilled. You can keep a much better eye on the seedlings, weeds weren't a problem, and the flowering was surprisingly abundant! Definitely give it a try! Just keep in mind that the plants get quite large and need support even in containers. I simply stick a few curved, thin willow branches around the edge of the container; it looks very natural.
Over the past few years, I've experimented extensively and below I present all the varieties of Cool Flowers that even a cold winter can't deter. Among the particularly hardy Cool Flowers for sowing in autumn are: Delphinium consolida (larkspur), Centaurea cyanus (Cornflower), Orlaya grandiflora (ray umbel), Nigella (Love-in-a-Mist) and Bupleurum rotundifolium (rabbit ear).
You can find detailed instructions for sowing here. here.
We've tried to find some truly special varieties for you again. Bright, garish colors aren't our thing, so this year we have what is probably the most beautiful poppy on the planet right now: 'Amazing Grey' Impressive in mystical grey-purple tones. Rudbeckia 'Sahara' It has perhaps the most incredible color spectrum: deep velvet red, caramel, ochre, and apricot-copper. Delphinium “Fancy Smokey Eyes” It shifts between silvery white and delicate lavender, a deep purple scabious This creates a bit of drama and the Irish shell flower It's a must-have in every cut flower garden. A stylish addition to any bouquet, but also beautiful on its own with its architectural and ornamental form.
I'm curious to see which will be your favorite flower!
