When I was a young boy, I came down with a terrible cold and was stuck at home for weeks. This was memorable for me because during that time, I was gifted a copy of C.S. Lewis’s Chronicles of Narnia. Those were the first books I remember getting hooked on and they were the gateway through which I entered the worlds of Tolkien and others. Of the many types of characters found within the pages of those books, I have always had a particular fascination with wizards. Now that I’m an adult, I’ve concluded that growing native plants from scratch is as close as I will ever come to being a real wizard, and it all starts with the powerful magic of seeds.

Seed Collection Guidelines

Before we discuss some basics of seed collection and introduce you to some local species, we need to address the potential harms that can be caused to native plant populations. With some basic knowledge and care, these impacts can be avoided. Below are three guidelines for responsible seed collection:

  • Never collect seeds from public lands, conservation lands, or private lands without permission.
  • Never collect more than 10% of seeds from a population each year.
  • Never collect seed from rare plant populations without advice from a professional biologist.

Seed Collection Timing

Growing plants from seed can be very efficient and is the recommended propagation method when possible. Some plants are notoriously difficult to grow from seed or are just plain easier to grow from cuttings. Successful seed collection is about timing and paying attention to plants throughout the seasons, and is a great way to learn about the life cycles of plants. Though there are some resources available for seed collection timing for local species, I believe it’s possible to successfully determine collection timing through observation and common sense. If seeds are collected too early, they won’t be fully developed and will fail to germinate and grow. If seeds are collected too late, there won’t be any there when you go to collect them. Finding the right window is easier for some species than others. Species like June plum and Saskatoon berry produce berries that are favoured by birds, so the window of opportunity to collect mature seeds is small. Other species, like yarrow, hold at least some of their seeds for months, so the collection window is more forgiving. The best rule for determining collection time is that when the seeds are naturally dispersing (by wind, bird, etc.), they are ready to collect. The seeds of most species will continue to develop after they’ve been harvested, especially if some of the plant tissues are still connected. For example, when we harvest seablush, we cut the stalks and put them in a dry paper bag rather than shaking off only the mature seed. This allows some time for green seeds to continue pulling resources from the stem as they mature. Seed collection times for some species are available here.

Seed Storage

Keeping seeds dry and cool is important to avoid mold. Seeds should be collected in dry conditions, not on rainy days or with morning dew. If seeds are still green or are collected with green stems, they will need to be allowed to dry in a cool place with good airflow. Once they are dry, they can be kept in paper envelopes. Longer seed storage is possible, and refrigeration is usually recommended. However, we find the best approach is to only collect the amount we need each year, and we don’t typically store seed for more than a few months.

Starting Seeds

To be successful with seeds you also need to know the conditions that will stimulate germination and allow young plants to grow. Most of our native plant seeds are adapted to germinate in the late winter after the worst of the cold temperatures are over, and in anticipation of spring growing conditions. Some species, such as annuals adapted to sites with prolonged seasonal drought, will germinate in the late summer or early fall and benefit from the short fall growing season. See an article on fall-germinating wildflowers here. Many native seeds will only germinate after experiencing a period of cold wet conditions, this is known as ‘cold stratification’. We find the best timing for sowing native species is September. We sow most of our seeds in open shallow propagation trays or 38-cell flats and leave them outside to naturally stratify. Annuals are best sown directly in gardens or restoration sites. Most species will germinate sometime between January and March. If sown in small containers the plants will need watering as we get into the dry season, and most will grow best when very young if kept in part shade or under a shade cloth.

Three Examples of Local Species to Grow from Seed

Seablush

Seablush seeds in the center are brown and ready to fall off. Seeds at the edges are pink or green and will benefit from staying attached to the step a little longer.

Seablush is a great plant for beginners interested in learning about seed collection. As a fall-germinating annual, you get results right away, and an opportunity to practice your seed collection skills the following June. Below are instructions for growing seablush from seed:

  • Seeds are ready to collect in early to mid-June. Hot dry sites are ready for collection before cooler shady sites. Seeds are ready to collect when some of the seeds are loose and ready to fall off on their own. Seeds will mature over a period of days or weeks, even on the same stalk. To maximize efficiency, cut stalks above the leaves, placing the entire flower stalk in a bucket or paper bag. Spread all your stalks to dry in a shady cool location. We dry them inside so the seeds don’t blow away in the wind.
  • Once the stalks and seeds are dry, gently shake off the mature seed, remove the stalks, and store the seeds in a paper bag.
  • Sow the seeds in late August, gently raking them into loose soil in a location with at least some winter sun. Seablush begins to germinate when cool nights bring morning dew. By the end of September you should have a low carpet of seedlings. Flowers will follow in April/May.

Small-flowered fringe cup

Small-flowered fringecup has small but intricately delicate florets. Photo taken by Richard Droker.

This perennial plant is a great addition to garden beds or natural areas. It loves semi-shaded sites and is reasonably drought tolerant. The seeds are ready to collect at the end of June (I collected some today – June 28th). The flower stalks bear multiple florets, which develop into small cups, each containing dozens of small black seeds. Stalks can be cut or bent over a container and the seeds will fall-out. It is easy to collect a lot of seed very quickly.

  • Seeds are ready to collect in late June. Tip seed heads into container. Store in paper envelopes.
  • Sow seeds in September in shallow seed trays. They will germinate in late winter.
  • Seedlings can be potted up into 1-gallon containers in May. They will flower in the following spring.

Camas

Camas bulbs can be removed from shallow propagation trays after two years of growth in August when they are dormant and moved to deeper boxes.

Some of the first seeds I ever collected were camas seeds. When I worked for Parks Canada we collected 198,000 seeds (yes I counted them… OK I counted a sub-sample, weighed it, and did some math). Those seeds collected in 2009 and 2010 were the beginnings of what is now an established Garry oak meadow at Fort Rodd Hill National Historic Site. It’s well worth a visit there in the spring to see the wildflower diversity. Camas are a relatively easy plant to grow, however, they require a lot of patience. Plants take five or six years to reach flowering size, but it’s worth the wait.

  • Seeds are ready to collect in late June or early July. You can tell they are ready to collect when the lower seed cups are brown and have opened up. You should be able to see the black seeds resting inside. Camas flower spikes mature from the bottom to the top, and seeds mature in the same order. Once the bottom seeds are ready, you can either pick off individual seed cups, or cut the whole flower stalk and keep it in a paper bag until the rest of the seeds mature.
  • Seeds can be sown at high density, 600-700 seeds (a large handful) per open shallow tray.
  • Seeds will germinate in January or February and seedlings will look like a blade of grass in their first year.
  • Camas do not require any watering. If you water in the summer you may cause the bulbs to rot.
  • After two growing seasons, dump the trays in August and pick out all the small bulbs. We then sow them in custom-made boxes with 10” deep soil. An important design feature of the boxes is a bottom that prevents the bulbs from migrating down into the underlying soil. We use old metal roofing, which allows drainage at the sides.
  • In the 5th or 6th growing season some bulbs will flower and can be planted in containers or garden beds.
  • There is no reason you can’t direct sow camas seed, other that they tend to get lost among other plants because they stay small for so long. Starting them in containers helps keep track of them until they are larger.

Bonus – arbutus seed cleaning video here.

Stay tuned for our next edition of Notes from the Nursery in November. We will discuss propagation from hardwood cutting in advance of the winter season.


0 Comments

Leave a Comment:

Your email address will not be published. Required fields are marked *