For the past four years, I’ve been replacing dozens of daylilies with more deer-resistant perennials, most of them started from seeds sown indoors under grow lights in winter. There have been great successes like the agastache (anise hyssop) shown above, and at very little cost. In addition to being the most affordable way to raise lots of new plants, starting hardy perennials from seed makes use of grow lights you won’t need for vegetables for quite a while yet.
The perennial treasures I’m after must be animal resistant, attractive to pollinators, easy to grow, and hopefully native. I’ve tried a dozen species with winners and losers, but then losers are to be occasionally expected with perennials. In the words of American horticulturalist Allan Armitage, “A perennial is a plant that will come back and grace the garden year after year, unless it’s dead.”
Perennials are always a gamble, but you can keep the stakes low by starting plants from seeds.
Starting Perennials from Seed
Most hardy perennials benefit from an early start because sturdy seedlings that are exposed to chilly spring temperatures often bloom their first summer. In addition, the seeds of some species require chilling to trigger them to break dormancy. Popular flowers including echinacea, black-eyed Susan, and many milkweeds germinate best when they are subjected to cold stratification, or about 60 days of moist cold. The easiest way to cold stratify seeds is to mix them with damp sand in labeled plastic bags, and store them in the refrigerator.
Or, try winter sowing in plastic bottles. The same techniques used for winter sowing hardy annual flowers work with many hardy perennials.
All this said, it has been my experience that most perennial flower seeds will germinate at normal room temperatures provided the seed is fresh and of good quality.
It’s more important to maintain moist conditions, which can be a challenge in winter when indoor air can be dry. Enclosing the seeded containers in loose plastic bags will keep them from drying out.
Seeds that haven’t germinated within three weeks probably aren’t going to, but you have little to lose by putting them in a protected place outdoors to let them fend for themselves. Flower seeds can surprise you.
Hardening Off and Transplanting Perennial Seedlings
Hardy perennial seedlings are often tiny little things that explode with growth after they have two or three true leaves. That’s the best time to prick them out into small containers where they can grow until they are rootbound. The seedlings should be moved outdoors in fair weather, and brought indoors during winter storms.
Hardy perennials tolerate light frosts, but it’s still a good idea to use cloches when setting out hardened-off seedlings in spring, and to set them out a few at a time rather than all at once. Cloches will protect the plants from wind and cold, and from curious nibbling by animals. Even animal-resistant species often get chomped on once. Staggered planting times can help evade underground marauders like chipmunks or mice, who are quite hungry in late winter.
If the plants like their new home, they will start growing rapidly as the soil warms in spring.
Discovering Old and New Species
One of the great things about starting with seeds is the huge selection of species you can explore. If you are looking to grow more native plants, I suggest starting with straight species that are native to your area. In addition to requiring little care, the plants are guaranteed to be of interest to insects. Last year my seed-sown wild verbena (blue vervain) pleased pollinators for months. The wild monarda was hardly touched by deer, but a cultivated strain growing nearby was not so lucky.
Working with seeds also gives you plenty of second chances. Sometimes a plant will show great promise, and then you’ll get just the wrong weather, as happened with a verbascum I tried last year. It deserves a redo, and I still have seeds.
Back to saving money. You will like most of the new perennials you try, but not all of them. Great. You didn’t blow fifty dollars on an ugly duckling. Nor do you have to keep plants that are simply disappointing. Instead, start something new, from seed.