Starting Perennial Herbs and Flowers from Seed
Some perennials can be challenging to start from seed, causing gardeners to shy away from perennials altogether, but many hardy herbs and flowers can be sown similarly to annuals and add so much beauty, flavor, medicine, wildlife habitat, and pest-protection to any garden.
Since perennials are more independent than annuals, they are slightly wilder by nature and do best if grown in conditions that mimic their natural environment. Plants that originate from a cold climate - like the north-east natives echinacea and lupine - prefer to go through a cold-spell before germinating, just as their uncultivated ancestors would by dropping seeds in the fall and sprouting the following spring. On the other hands, varieties native to warm climates, like the Mediterranean native rosemary, need a warm, somewhat arid environment for best germination.
To add perennial beauty to your garden this year, sow them similarly to annuals, but considering the tips below. For a full Guide to Seed Starting, take a look at our collection of resources. To get ideas on which perennial herbs and flowers to add to your growing plan, scroll down for a list of our favorite varieties.
- One option is to sow them between late fall to early spring and simply let them go through a real winter. The advantages of this method are that the seeds will get a head-start on root development and growth and may even bloom in the first season. They will also better adapt to the particularities of the region by starting their life directly in that environment. Some disadvantages are that a few seeds will succumb to the perils of winter and outdoors sowing and may get washed away by rain or eaten by birds.
- Another, more controlled, method is to mimic winter by giving the seeds a cold treatment to encourage germination. That’s called stratification and is written about in Erin’ Winter Sowing guide.
- When seeds grow without human intervention, most aren’t planted. Instead, they fall to the ground and germinate right from the surface. Because of this, some perennials need light in order to germinate. Check the seed packet for germination light requirement. If light is needed, rough up the surface of your seed-starting pot with your fingers and sprinkle the seeds directly on top.
- If no light is required, sow your perennials the way you would any other seed: two times as deep as the seed is tall.
Sow Patiently. Most perennials are slow pokes. Unlike annual plants that race to live out their entire lives in one growing season, perennials are in no rush to mature.
- It is typical for a perennial herb or flower to take three or even a month to germinate. Some varieties won’t germinate all at once, which means each seed from the same source may sprout over the course of a couple of weeks.
- Once germinated, perennials can be slow to grow. Some devote their first season to growing roots and storing nutrients, which means gardeners may have to wait till the second season for flowers to bloom or herbs to develop big, bushy foliage.
- To get the most growth in the first growing season, start perennials indoors eight to ten weeks before your last frost date. It helps to label each pot not only with the variety name, but average days to germination and the date of sowing.
- If you, like the plants, are in no rush, perennials can be direct sown after the first frost date. As with any seeds - keep them moist until they germinate.
Great perennial herbs and flowers to start from seed:
Herbs: anise hyssop, catnip, chives, garlic chives, sage, thyme, oregano, lovage, salad burnet, tarragon, arnica, echinacea, yarrow
Flowers: echinacea, yarrow, hardy hibiscus, johnny jump-up, perennial sunflowers, lupines, penstemon, english daisy