Do you feel you don’t have the nerve, time or skill to germinate perennial seeds? Don’t worry. You’re not alone. Step right this way. I’m going to show you how easy and how much fun sowing perennial seeds can be.
The love of gardening is a seed once sown that never dies
-Gertrude Jekyll
I worked for Jelitto Perennial Seeds for 22 years and learned a few tricks. I am a little biased. The good people at Jelitto, upon my retirement in 2018, gave me the passcode to their seed bank and free seeds for life.
Sandwich baggies with perennial seeds and medium-grade perlite, undergoing a six-to-eight week cool-moist treatment, prior to sowing in sand beds.
I love to sow seeds, not only for perennials, but also for trees, shrubs, bulbs, annuals, and vegetables. Yes, there are always a few pitfalls. Seeds can be overwatered or underwatered, and seedlings die, but the act of seed sowing is an inexpensive way to grow your own plants. It’s worth a shot.
Let’s cut a few corners
You won’t need a greenhouse, cold frame, grow lights, or water jugs. You need only seeds, plastic sandwich baggies, medium grade perlite or fine sand, and a little room in your refrigerator or a cool garage.
Some perennial seeds germinate evenly in a greenhouse, within weeks—like hair on cat’s back— with temperatures hovering around 68 F (20 C). Here’s one idea: You could wait and choose to sow these seeds directly in an 8″ sand bed a few weeks before last frost and let nature do the rest. Other perennial species may geminate unevenly over 4-6 weeks and benefit from a moist-cold stratification for 6-8 weeks. The sand bed is good for these seeds as well.
Other trickier species need to be sown fresh upon ripening. Still others may have to overcome the female dominatrix, triploid endosperm, to germinate. No need to go deep into the weeds, or bore you, with seed physiology.
Germination tips for every Jelitto seed item, are featured on the last few pages of the Jelitto catalog. Download catalog here:
There’s an alternative and easy way to sow most perennial seeds
At this time of year, there is a simple germination technique. It will work whether seeds are bought from seed companies; are a member’s perk from North American Rock Garden Society’s Seed Exchange; or are harvested seeds free-for-the picking from your garden.
Place your perennial seeds this winter in sandwich baggies mixed with moistened medium-grade perlite or fine sand.
Dianthus isensis ‘Dancing Geisha’ is a mix with fringed blooms in white, pink, purple and red shades. Mary Vaananen photo.
Put the seed baggies in a box, seal it up, and place in a refrigerator or a cool garage for 6-8 weeks. Check the bags every week or so to be sure the mix is still moist. Spray water, but don’t drench. There may be a few surprise seedlings. You can prick these out, pot them up, and place on a sunny windowsill.
There are often advantages to having temperatures that fluctuate up and down, so the garage is my preference. Even a few degrees of frost won’t hurt anything.
Allow 6-8 weeks of this cold-moist stratification that mimics variable outdoor winter conditions. Then, afterwards, go ahead and spread the seed mix in an 8″ sand bed. (Imagine a child’s small sand box 3’ x 3’.) Barely cover with sand, and then water.
Germination will begin as spring unfolds
I try to thin out sand-bed seedlings in May, and plant them in the garden, but I don’t always get to this. The perennial seeds root into the sand bed, fight for control, and the survivors will be planted the next spring. The 8” sand beds inhibit considerable, but not all, weed seed germination. Summer watering requires a little vigilance, but it’s fun to check regularly on your seedling nursery. The sand beds do dry out, but the perennial seedlings will penetrate deep into the beds where moisture is pulled from the ground.
Heliopsis ‘Burning Hearts’ with a milkweed bug. Mary Vaananen photo.
Perennial seed recommendations
I asked Mary Vaananen, Jelitto’s North American Manager and popular Garden Rant guest contributor, to recommend a few Jelitto Perennial Seed selections that can be sown with moist medium-grade perlite, or fine sand, in sandwich baggies this winter. Mary confessed. She hadn’t started seeds in baggies. She prefers, like many gardeners, to grow easy-to-germinate perennials on a sunny windowsill where she can keep a close eye on her babies, but the baggies would work with her pick hits, also.)
Mary Vaananen in a Jelitto seed packet costume made by Jaime Manlove of North Creek Nurseries.
“Cymbopogon flexuosus (east Indian lemongrass) is one of my go-to herbs every year. I usually sow them in March indoors and then transition them outside gradually to a protected place, so they get enough light to grow straight before transplanting. Very easy and quick to germinate.
“Heliopsis Burning Hearts is one of the most cheerful flowers in my garden. Uncomplicated and easy to grow from seed, it even seems to flower well in the dappled shade I garden in. In more sun, the leaves are a burgundy color which adds to its ‘look at me’ factor. If you fall in love with ‘Burning Hearts,’ you will probably have to try ‘Bleeding Hearts’ too. Deep red-orange flowers that fade to dusty orange bronze.
“Dianthus ‘Dancing Geisha’ has unusual flowers with drooping shredded petals…really cool! Another easy to germ perennial that flowers the first year from seed. ‘Dancing Geisha’ is a color mix of pinks and purples, red and white.”
Mary adds a last piece of advice
“Transitioning new seedlings from indoors to outside must be done over a bit of time, being conscious of the light and temps. You don’t want to shock tender seedlings with too much sun or cold (or heat). Definitely keep them out of direct sun when first giving them outside exposure. A shaded area for the first week is good. Be mindful of temperature. If you feel comfortable going outside in the spring (from indoor temps), the seedlings will probably too. Low to mid 60s should be safe.”
Different ways to skin the cat.
You’ll never know the joy of little seedlings unless you try.
Let me know what works for you.