Our Favorite Hardy Annuals
Happy 2020! We hope that you are all doing well and are well on your way to planning your flower farm and gardens for next year.
As we start off the 2020 growing season, there are some varieties of plants that we’ll have to start earlier than most - plants that do the best with a long and cool establishment period that late winter and early spring brings.
These plants - hardy annuals technically - are hardy to much lower temperatures than tender annuals like zinnias and dahlias and sunflowers are. While a dahlia will turn into mush as soon as even a light frost hits, these hardy annuals will thrive in cool, even freezing conditions.
These are also the annuals that if planted late in the spring will go to flower very quickly - on short little stems with pathetic little blooms and very quickly die in the heat. Not really the tall, beautiful opulent flowers that you want to enjoy in the garden or cut for the vase.
Especially if you’re a flower farmer, you’re going to want to ensure that you get these hardy annuals started early and into the ground as soon as possible. Certain hardy annuals like bachelor buttons, daucus and poppies are more hardy than others like Queen Anne’s Lace and cerinthe, so make sure that you research the hardiness of your annuals (check out this post on starting a flower farm from seed including a helpful cheat sheet for hardiness of annuals)
Here are some of our favorite hardy annuals we grow every year!
Scabiosa (Scabiosa atropurpurea)
Scabiosa - also known as pincushion flower due to the appearance of its mounded bud and white pin-like pistils is a very easy annual to start from seed. Partially because the seeds are large and easy to handle, partially because the seeds are very vigorous and start grow into a large plant very quickly, and partially because they are pretty hardy so long as you keep them in relatively well-draining soil.
We love scabiosa for their ability to add that wonderful wildflower esthetic in bouquets and arrangements as well as that British wildflower-esthetic when seen in the field. Our favorites include ‘Dark Knight’ - a lovely dark plum/burgundy color that from my experience is the most vigorous and has the thickest and longest stems - as well as ‘Snow Maiden’ - a pure snow-white variety that is perfect for wedding work (seen here).
If you’re interested in growing scabiosa, definitely read our guide to growing scabiosa for flower farmers
Clary Sage (Salvia viridis / Salvia horminum)
Clary sage (Salvia viridis or Salvia horminum depending on which horticulturist you ask) is a wonderful colorful and hardy annual that is one of our favorite spring annuals to grow. Not to be confused with the massively stinky herb clary sage (Salvia sclarea) clary sage will send up long spikes of white, pink, and purple flowers that are the perfect addition to floral arrangements and bouquets.
A pretty hardy annual (overwintering well in even below-freezing temperatures) so long as you provide well draining soil, it will send up the tallest and most usable stems having put on a very large and great root system during the long and cool establishment period. It will start off as a large basal rosette of silvery-green sage-y foliage (can’t really think how else to describe it!) that will then explode into bloom all at once.
The best part? If you continue to keep it deadheaded it will continue to bloom for you all the way through the growing season, providing plenty of color and texture for your arrangements all season long.
Verbascums
Verbascums (also known as mullein) are an excellent cut flower with gorgeous colors and a wonderful tall airy vertical form that are relatively unknown in the United States. Used heavily by British gardeners (usually in the form of the silvery garden variety Verbascum bombyciferum) I wanted to give verbascums a try as a cut flower and they did not disappoint!
Although technically a biennial (and in some cases an actual true perennial), I usually treat verbascums as a hardy annual since they flower best the spring after a fall planting. By planting them out in autumn and allowing them to get established before the winter sets in, they will be ready to go in springtime.
And boy do they put on a show! Tall, 36” spires with light and airy blooms, they remind me of a vertical garden phlox - except for the fact that they open from the bottom to the top. Although each individual floret is not necessarily long lasting, the entire stalk will last over a week in clean water since it will continue to bloom all the way up the stalk.
‘Phoenicium Mix’ is my favorite with dark purple, deep pink, light pink and pale white spires that mix well with all the other hardy annuals of spring, but if you’re looking for a real showstopper ‘Southern Charm’ has beautiful soft antique rose and peach and ivory cream flowers with rosy centers - similar in color scheme to the Phlox drummondii variety ‘Cherry Caramel’.
Icelandic Poppies (Papaver nudicaule)
If you’ve been following our blog for any length of time, you know that I’m crazy about poppies - and Icelandic poppies in particular. Their lovely crepe-paper textured petals, wonderful mixture of bold and soft romantic colors, their wonderfully soft and delicate form are all redeeming qualities for why we love them for floral design and arranging.
However even better is the fact that they are extremely cold hardy - one of the hardiest annuals we grow actually - surviving temperatures well into the teens, shrugging off frost and freezes and snow and ice and earning their ‘Icelandic’ title and more. I’m also ashamed to admit that I’ve also inflicted abuse on countless poppies over the years - underfertilizing them, underwatering them, overwatering them, leaving them far too long in their trays until their leaves start going chlorotic from a lack of nitrogen - and they’ve gone on to still produce a prodiguous amount of flowers for us.
Icelandic poppies are wonderful producers too, sending up armloads of the delicate flowers on thin velvety stems. So long as you keep them well fed and watered they continue to produce for us well into June, earning more than their keep on our flower farm. Our favorite cultivars are the prolific ‘Champagne Bubbles’ as well as the giant Italian Colibri poppies. If you’re interested in learning more on growing Icelandic poppies, check out our growing guide on growing Icelandic poppies stress free!
Black Eyed Susans (Rudbeckia hirta)
If you’ve never grown rudbeckia as a hardy annual - planting them out in the fall and letting them grow and get established over the winter, they are a spectacular treat when they start blooming in early summer. As opposed to the little stunted plant that you usually find at nurseries, these big and fluffy specimens are wonderful for bouquets and arrangements.
Rudbeckia seeds are a little bit slower to germinate, but once they get going they are very hardy and very tough plants that can withstand heat, humidity and all matter of stressful situations and keep on growing and blooming. These also aren’t your grandmother’s black eyed susans either - with the new varieties like ‘Chim Chiminee’ (seen here with its eyelash-like petals) or the soft chocolate and gold and rust colored blooms of ‘Sahara’ or the bold and brilliant and showy forms of ‘Cherokee Summer’ they are a completely different breed of flower (although I’m still very partial to the good old ‘Indian Summer’ with the traditional black center and large yellow petals).
Hardy down to zone 3, rudbeckia are very hardy so long as you keep them in relatively well-draining soil. You can even use row cover or mulch them with leaves if you need to, but in most cases they will survive just fine on their own.
Interested in learning more on growing hardy annuals?
Feel free to download our free eBook on Seed Starting for the Flower Farmer - a full book on starting a flower farm entirely from seed including our equipment, techniques, successions, growing out, hardening off and transplanting, as well as a detailed guide to germination for specific species. An excellent read for the beginning flower farmer new to seed starting!
Check out our growing guide on 10 cut flowers you should be growing for next spring for more hardy annuals you can start for next year!
If you’re interested in learning more about starting hardy annuals (and other plants and flowers) from seed, check out our guide on starting a flower farm - all from seed.
If you’re interested in growing some of the hardy annuals that can be trickier to start from seed (including larkspur, bupleurum, Bells of Ireland and nigella) as well as more perennials, you may want to check out our post on cold stratification and helping more difficult seeds to germinate
There are also a lot of growing guides for each individual species or variety that we share our experience on growing:
Lastly, we also did a podcast on starting hardy annuals from seed that you can listen to here!