Back Issue
January/February 1998

Easy Perennials From Seed
by Andrea M. Masisak

Some people experience post-holiday blues, I get the greens. It's a relief when the manufactured merriment of the holidays has passed and I can joyfully contemplate my new seed catalogs. Far from being a depressive malady, the greens are a state of hope in which I'm one step closer to the challenge and promise of the upcoming season.

The rewards of starting plants from seeds are many — quantity, variety, rarity, monetary and, not least, a sense of accomplishment. I can raise plants for pennies, which allows me to sample widely and to try rare plants not usually available at local nurseries. If I need to fill large area quickly, I don't have to spend hundreds of dollars to do so. This allows me more money to spend on plants that I cannot raise from seed. And unlike an expensive plant purchase that I feel compelled to suffer with, if a plant doesn't perform or if I tire of it, out it goes. For example, 12 pots of Achillea 'Summer Shades Mixture' from a noted nursery cost over $55. A packet of 100 seeds of Achillea 'Summer Pastels' (a similar mixture of shades) cost me $2.95, and I still have seeds left. When I tired of the plants, I felt no guilt about pulling them out. If I'd paid $55, they would still be in the garden.

I've been raising perennials from seed for six years and have found them to perform equally as well as their store-bought counterparts. Seedlings may take a bit longer to establish themselves in the garden, but even a larger purchased plant will take a season or two before putting on its best show. Some perennials, such as Coreopsis grandiflora and Shasta daisy and the grasses Miscanthus sinensis and Pennisetum alopecuroides, will grow and flower abundantly in their first season. It's much more common to see the fruits of your labor in the second season when you will be rewarded so generously that even gardening friends will be surprised to learn you started from seed.

Plants grown from seed are surprisingly tough and seedlings are not the delicate darlings many believe. The ornamental grass Miscanthus sinensis is a case in point. Several years ago I planted two wispy seedlings. I never fertilized, but they grew to 4 feet by fall and even produced seed heads. Last spring I pried them out of the ground leaving behind two large craters. One plant was so heavy I needed help getting it into the wheelbarrow, and several months later it was still alive on the compost heap.

I start most of my perennials at the end of February, and they are usually ready to be hardened off and planted by mid to late May. Seed starting is not an exact science and germination and growth rates vary greatly among plants. Consult the seed packet for specific instructions, although I've successfully germinated seeds that supposedly required either heat or cold to germinate without providing these conditions.

While it's true some specific varieties can only be vegetative propagated (Coreopsis 'Moonbeam') or are highly variable form seed (Heuchera 'Palace Purple') most perform beautifully.

Seed Starting Supplies
I have raised perennials in a commercial greenhouse using basic plastic trays, and at home using a Floralight and a self-watering mini greenhouse system known as the Accelerated Propagation System (APS), which I set up at the back of the living room. While growing in the greenhouse afforded space and yielded good results, I have found the APS units to be virtually foolproof for the home grower, especially those of us with limited space. APS systems are available at some nurseries, but the Gardener's Supply catalog (1-800-863-1700) has the widest selection of sizes and a good selection of Floralights.

The Floralight can be used for houseplants as well as seed starting and the APS units will last several years if given reasonable care. With the number of plants I was able to start, I recouped my initial investment in a season or two.

The APS unit is an insulated growing tray divided into square cells, sizes vary depending on the model chosen. It has a clear greenhouse cover, a water reservoir, a pegboard, and capillary matting which continuously wicks moisture from the reservoir and delivers it to the growing tray. The system fits together in a neat self-contained unit, and I can easily fit four APS 40-cell units under my 4 foot tabletop Floralight. If I get total germination, the rewards can be truly staggering.

When initially starting seeds in the APS, I use a soilless seed starting mix such as Jiffy or Peter's that is weed and disease-free, and I pre-moisten the mix before using. A soilless mix is important because the greatest threat to emerging seedlings is the soil-borne disease called damping off, which causes sudden death. By the time seedlings are big enough to be potted up, damping off is not a big concern.

To minimize the changes that your seedlings will succumb to damping off, make sure that all of your seed starting materials are thoroughly clean before use. After using the APS, soak all parts in a diluted beach solution (one part bleach to nine parts water), rinse, dry and carefully store.

I use 40-cell units for perennials, sowing two to four seeds per cell to increase my odds of germination. Even if only one seed per cell germinates, that gives me 160 seedlings and potentially 640 if all four germinate. Total germination is rare, but I have risen up to 200 seedlings at one time. I am limited by the size of my one Floralight because when it comes time to pot up my seedlings I only have light space for 100 plants at a time. The year I raised 200, I kept the light on for 24 hours a day and rotated the seedlings every 12 hours. I now try to keep my seedlings production down to manageable levels. The moral of the story is to make sure that you have the light and space to accommodate your seedlings as they grow.

Caring for the Seedlings
Once they have their second set of true leaves (the first set are seed leaves called cotyledon and shouldn't be counted), I pot each seedling individually into clean plastic pots. I use a prepackaged potting soil, which I further amend with additional perlite to improve drainage and premoisten before using. Normally, I use 2-1/4 inches square pots, but extensive root systems can require a larger pot. You'd be surprised at what a large root system a very small seedling can produce, and a larger 3-inch pot may be needed to accommodate this larger root system. After you've potted up your seedlings, give them a thorough but gentle watering to settle the soil and collapse any air pockets.

If you want to grow the seedlings on in the APS, you will have to thin them out. Use baby scissors to snip off the extras. Don't pull them out because you risk damaging or uprooting the ones you want to keep. Feeding with a seedling fertilizer, such as Roots Plus for Seedlings, can be done by adding one tablespoon to the APS reservoir.

Seedlings will continue to require 14 hours of light per day and should be kept no more than 2 to 3 inches from the bulbs. The goal is to produce strong, stocky seedlings not weak, spindly ones. Times are available to control your light automatically. There are expensive fluorescent bulbs that promise to deliver a broader spectrum of light, but I get great results using one warm and one cool fluorescent bulb. Some seed starters use a small fan to create a gentle breeze. Air movement is said to reduce the change of fungal diseases and to stimulate growth hormones in the plants. I've never used a fan, but I light brush my hand over the plants at least once a day. Room temperature is kept between 60 and 66 degrees with low humidity.

The APS is self-watering, but once the seedlings are out of the unit you must be attentive to watering and occasional feeding with a seedling fertilizer. This minimal monitoring is hardly a chore. I'm amazed and captivated by the lushness and growth my seedlings exhibit during the bleakness of late winter and early spring — it's a joy to watch and gives me a great sense of accomplishment.

By using the APS and a good light fixture, the perennials I have suggested should be easy to grow from seed. If some are still too small to transplant in the spring, I continue to grow them on outdoors through the summer, potting up as needed, and planting in the early fall. Once they are planted outside, I'm not one to pamper my seedlings; aside from basic tending they have to make it on their own. My biggest problem is felonious felines who smother young plants when digging in the mulch.

Selecting seeds
Plant catalogs, nurseries and gardens provide inspiration for what I'll start from seed. When I see a perennial that strikes my fancy, my first thought isn't where can I buy it, but are seeds available? One of the most comprehensive sources is the Thompson & Morgan seed catalog (1-800-274-7333) listing hundreds of perennials by genus and species, including the very rare. Park Seed (1-800-223-7333) is another favorite. Many horticultural and plant societies offer members free seed exchange programs. The benefit is not only access to unusual varieties, but the knowledge and experience of members who have raised them.

Many named varieties are available from seeds: Echinacea 'Magnus' (1998 Perennial Plant of the Year), Hollyhock 'Nigra' and 'Chatter's Double Apricot', Penstemon 'Husker Red' (1996 Perennial Plant of the Year), Dianthus 'Zing Rose' and, though not named, you can find seeds of the most genus and species for plants found in the most exclusive nursery catalogs. For example, last spring White Flower Farm offered Dictamnus albus (the white-flowered form of gas plant) for $19.95 each. I bought a pack of 20 seeds from Thompson & Morgan for $2.49.

For economy's sake, I see no point in buying any perennial I can possibly grow from seed, especially when there are so many tempting plants, like woody ornamentals, that I'm unable to grow. The financial incentive may have started me on seed starting, but the rewards of raising my own plants are far more than monetary. There is an overwhelming sense of pride and amazement when I look at what I've grown. This year banish the blues with some seed starting — your success will make your friends green with envy.

Andrea M. Masisak is a freelance writer and a Master Gardener certified by UConn's Cooperative Extensive System.

Easy Perennials to Grow from Seed

Common Yarrow Achillea millefolium
Sneezeweed Achillea ptarmica 'The Pearl Superior'
Butterfly Weed Asclepias incarnata 'Ice Ballet'
Garden Columbine Aquilegia vulgaris 'Nora Barlowí' and 'Music' hybrids
Tussock Bellflower Campanula carpatica
Valerian Centranthus coccineus ruber and alba
Snow-in-Summer Cerastium tomentosum
Tickseed Coreopsis grandiflora 'Early Sunrise'
Delphinium Delphinium 'Magic Fountain Mix', 'Dwarf Blue Butterfly'
Maiden Pink Dianthus deltoides 'Brilliancy' and 'Ipswich Pinks mixed'
Dianthus Knappii
Foxglove Digitalis grandiflora and mertonensis
Coneflower Echinacea purpurea 'Bravado' and 'White Swan'
Fleabane Erigeron speciosus 'Blue Beauty'
Spurge Euphorbia polychroma
Blanket Flower Gaillardia grandiflora 'Goblin'
Grasses Miscanthus sinensis and Pennisetum alopecuroides
Flax Linum narbonense 'Heavenly Blue'
Cardinal Flower Lobelia 'Fan' hybrids and L. siphilitica
Musk Mallow Malva moschata 'Zebrina'
Beard-Tongue Penstemon 'Husker Red' and 'Cambridge Pastels'
Cinquefoil Pontentilla Thurberi amorubens 'Monarch's Velvet'
Pontentilla nepalensis 'Miss Willmott'
Coneflower Rudbeckia fulgida 'Goldsturm'
Sage Salvia superba 'Blue Queen'
Lamb's Ears Stachys lanata
Stokes' Aster Stokesia laevis
Chrysanthemum Leucanthemum superbum 'Snow Lady'
Primrose Primula polyantha 'Gold Laced'

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