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COOL KIDS | When the going gets tough, the tough get going

So, here’s a perfect example that you never stop learning in life – and the garden. Last year was the first time I stumbled across Hardy Annuals, also called Cool Flowers. It’s a concept that’s little known here in Germany, even though nature shows us how it's done every year.

Sweet Pea "Hi Scent"

And the best thing? Right NOW, when we’re lovingly looking at the last of our summer blooms and longing for spring, when we can start our annual seedling Kindergartens all over again – THAT’S when the time to sow Cool Flowers is just right.

So, who are you, Hardy Annuals?

Hardy Annuals (often abbreviated as HA) are annual plants that don’t just tolerate the cold, they positively thrive on it. Depending on just how freezing the winters are where you live, they can be sown already in the fall or in early spring. Some frost here and there doesn’t bother (most of) them; in fact, it helps develop a strong root system which means they blossom significantly sooner than their counterparts.

Love-in-a-mist "Miss Jekyll"

It’s a concept that’s particularly popular in England – possibly because their winters tend to be on the milder side so that you don’t have to spend too much time fretting over how your plant babies are coping in the cold. And they do!

The term Cool Flowers was coined by Lisa Mason Ziegler, an American cut flower farmer who has been knee-deep (quite literally at times) in all things HAs.

So, in short: Cool Flowers are Hardy Annuals that can already be sown in late summer/early fall (or spring, see above) where they sit out the cold winter months in their flower beds outside, getting ready to kick-off spring in full force.

And they really cope?

They do! Just think of nature: when cornflowers, snapdragons & co self-seed, they do it all by themselves on fertile soil. Once the seeds start to germinate in the fall, the youngster seedlings have to be brave and strong on their own.

The oh-so-very-beautiful Orlaya Grandiflora

So, how do I sow them?

Why not try both, sowing in the fall and the early spring months? I'm a big fan of trial & error and I’d love to hear how it worked out for you! Care to share?

As a rule of thumb:

Hardy Annuals can be sown 6 to 8 weeks BEFORE the FIRST frost or 6 to 8 weeks BEFORE the LAST frost. You can plant them inside as well as outside. Some are better off being sown straight outside as they don’t take too well to being moved (see list below).

All the others:

I’d recommend starting early spring and inside. Firstly, because I love that time of year when it’s still too ‘meh’ for outside-gardening, yet the longing for greenery is so great that ‘hyggelig’ (as my Danish friend would say) inside-gardening feels like a perfect compromise. And secondly, because seeds simply germinate quicker in the warmth.

Of course, outside is an option! It just means you’ll have to wait a little longer for blossoms to show.

Yarrow "Summer Berries"

However, there are a few frost-hard types: cornflowers, foxgloves, yarrow, and Iceland poppies, to name a few. All others do need a little bit of protection, something like a fleece works really well. Some examples are: snapdragons, stocks, Orlaya grandiflora (also called white lace flower), or sweet peas.

You can use egg boxes, small pots, quelltabs, toilet paper rolls, tins (you need to drill holes into the bottom), or anything else you can find hanging around your house.

Potting soil is best – it’s got low nutrient levels and is sterile. Theoretically, you can make it yourself but, full disclosure, that’s too time-consuming for me. It’s ideal to place your pots onto a heat mat; it’ll make sure the temperature is just right and reduces humidity, which in turn minimizes the risk of fungus. It will also work without that though – you may just end up with fewer seedlings. Either way, make sure they are well ventilated.

Almost more important when starting early is a grow lamp. I got myself one a couple of years ago, and my seedlings tend to be stronger and healthier.

When inside, they should get around 16 hours of light. Again, you can of course do without. In that case, they must be in a light place, like a windowsill. Here’s a DIY tip: to avoid your seedlings growing too much towards the light, put them in a cardboard box, cut out the window side, and stick tin foil on the opposite side. It’s a simple trick to help reflect the light.

Statice "Pastel Mix"

Once your plant babies are about 10cm (4”) tall, they’re ready for life outside. Help them get used to their new environment over a few days though, so the temperature drop isn’t too much of a shock. A garage with the door left open or a shed is perfect.

And lastly: protect them with fleece for the first two weeks until their roots are a little more settled and robust.

These are some of the Hardy Annuals:


Feverfew (Tanacetum parthenium)

Pot marigold (Calendula officinalis)

Stocks (Matthiola)


Khella (Ammi visnaga)

Bells of Ireland (Moluccella laevis)


Black-eyed Susan

Corncockle (Agrostemma githago)




Strawflower (Helichrysum)


Sweet peas

These ladies prefer to be sown straight outside:

Corncockle (Agrostemma githago)




White lace flower (Orlaya grandiflora)

Iceland poppies


Snapdragon “Lavender”

AND: as this is such a new topic for me, I’d love love love to hear your Cool Flowers experiences. Send me an eMail to

If I've piqued your interest and you'd like to know more about all things Hardy Annuals, I can highly recommend Lisa Mason Ziegler’s book “Cool Flowers”. It’s the inspiration behind this post.

And last but SO not least – one of my absolute favorites: Daucus carota “Purple Kisses”.

Love from the Cottage Garden,


All photos (apart from the snapdragons): Janina Laszlo.


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