native plant sales

A History of the Plant Sale

By Sue Theriault

This article first appeared in our publications WildfloraRI, Fall 2021

Sandra Thompson (photo ARaver)

The loss of our dear colleague and long-time plant sale coordinator Sandra Thompson prompted me to reflect on the evolution of RIWPS’ plant sale through the years. Sandra was passionate about the propagation and sale of native plants and has left her mark on both Seed Starters East and what has become known as the “Best Native Plant Sale in Rhode Island.” With her loss, it feels like Seed Starters East and the plant sale are beginning a new chapter.

But to look ahead, it helps to first look back. And who better to help do this than board member Dorothy Swift, a founding member of both RIWPS and Seed Starters East. Dorothy was the first program chair when the organization began in 1987, and soon after Lisa Gould, the society’s first president, accepted an invitation by the URI Cooperative Extension to host an information booth at their Spring and Fall Festivals. They saw it as a chance to promote the fledgling organization, to hand out information on native plants, and to sell a few plants that RIWPS’ volunteers shared from their gardens — some plants were native to RI, some native to other places, and some cultivated perennials. Thus, the plant sale was born!

Early on, Dorothy had an idea for a seed propagation program. Dorothy was no stranger to propagation; she had grown rhododendrons through tissue culture and cuttings with Mike Medeiros at Plane View Nursery. But she wanted to try seeds and hoped some members would also be interested. In 1991, she and Joan Pilson, then program chair, held their first propagation meeting, which attracted about 14 people. “We planted cardinal flower seeds. When we met two weeks later and saw they had germinated, we were hooked!” Seed Starters East was born.

Dorothy Swift (photo ARaver)

“In the early years it was a struggle — we were a bit like the blind leading the blind,” Dorothy said. Only about three to five volunteers would show up for each work session. “Often the seeds would get too cold, too dry or too wet to sprout.”

Since those early days the annual sale has grown beyond a few plants at an information booth. RIWPS moved its sale to a larger space on the URI campus and became independent of the Cooperative Extension festivals. Over the years its inventory has grown to a few thousand plants, some grown by Seed Starters East and West, some dug, some grown from cuttings, some grown by volunteers, and some purchased from commercial nurseries.

When URI began construction on its new Coastal Building, the sale moved to URI’s East Farm. The larger space allowed RIWPS to supplement its inventory of perennials with native shrubs and small trees. “We got ever more organized as we created sections for shade and sun plants, groundcovers, grasses, shrubs and trees.” An ‘Ask the Experts’ table was set up where a few knowledgeable members answered questions and offered tips to the attendees.

By 2013, Sandra Thompson had taken over as plant sale chair of “The Best Native Plant Sale in RI.” (Certainly, no other RI organization couldbeat the variety and quantity of native plants that RIWPS offered!) To increase inventory even further, Sandra emphasized digging, because, as Dorothy put it, “if you have a wild plant at all you probably have plenty of it!” Sandra organized digs, on private land with the owner’s permission, and sheltered the newly potted plants in her driveway until the sale. Sandra had a knack for sharing her passion and knowledge with new volunteers. I, myself, was fortunate enough to work with her for a year at Seed Starters East and to accompany her on a dig. I remember nervously handling the shovel under her watchful to dig and, as a novice, I hoped I was doing it properly.

The early struggles of growing plants from seed have given way to even more successful approaches. RIWPS volunteer Peggy Buttenbaum tweaked the winter sowing method used by the growing group of volunteers. Seedlings that emerge in the spring are potted up and usually grown on for another year before being sold.

Today’s inventory reflects RIWPS’ evolution from the days of offering an eclectic mix of plants from all over the world to selling only those native to the eastern US and primarily to Rhode Island. The group is also using seed sourced locally as much as possible to capture the local ecotypes. Each plant label indicates if a plant is native to RI with the initials RIN or native to New England with NEN or native to eastern North America with ENA.

Why include non-Rhode Island natives? “A good example of a non-native we include is the flame azalea, whose range is a little farther south, because its bloom is yellow through orange to red,” says Dorothy. “All the rhododendrons native to RI (the rosebay, pinxterbloom, early, and swamp azaleas) are white, pink or purple.” The same is true for wildflowers. The color orange is rare in the native RI palette, except for a few species like butterfly weed. Including information on a plant’s origin on labels was one of the many contributions made by Linda McDaniel, who followed Sandra as plant sale chair. Linda led the plant sale through two ‘normal’ years and then two pandemic years and continues to be one of the leaders of Seed Starters East.

As Sandra was her mentor, Linda has been mine as I take on the role of plant sale chair. We worked together on the June 2021 online sale and

Sue Theriault (photo PLacouture)

built on the work done by so many in the previous year to get the sale on line. About 170 RIWPS members made purchases in June for total revenues of around $22,000. The fall sale at the end of August at the Pawtuxet Farmers Market — our first in-person sale in two years —brought in more than $9,000 in sales.

But the sales are not just about raising funds for RIWPS, they are also about education. I overheard Linda, as she stood behind a table filled with milkweed offerings, explain that the plant is the sole food source for the monarch caterpillar, but that the adult butterfly can obtain nectar from a variety of plants. It’s these personal interactions that make in-person sales so valuable. I look forward to 2022 being a year where we are back to our open-to-all, in-person sales in May, June, and August.

When I asked Dorothy how she saw the future of the plant sales her response focused on propagation. “I’d like to see us growing some of the more difficult plants from seed, like the native blazing star, Canada lily, and maybe even fringed gentian. And to increase our use of locally sourced seeds.”

I congratulate her — and all of us — on the group’s 30th anniversary. She offers us a bridge to the past as we move into the future, with people like Sandra Thompson in our hearts.

Cardinal Flower: Keeping it in Your Garden

—This article by Dorothy Swift first appeared in our publication WildfloraRI, Fall 2021

Cardinal flower (Lobelia cardinalis) is a favorite wildflower. But, in order to have it flourish on your own land, you must do some planning before you plant and care for it.

Here are some tips for maintaining cardinal flower in the Rhode Island region, based on my own trial and errors. Some of this experience was acquired since my earlier article about cardinal flower and its ability to attract hummingbirds (Wildflora, Spring 2015).

photo GGardner

Most reference materials state that cardinal flower prefers wet areas in partial shade. This is true for the southern United States. The part about moisture is true for plants that self-seed in the wild, and must compete with other species in order to proliferate. You will commonly find wild cardinal flower in ditches and other moist places. However, in cultivation, I have found that sunny areas with normal good soil and drainage are just fine for plant growth and flowering.

Aim for some clear sky above to provide good light, though there can be some shade from distant trees or dwellings. Plants placed in a shaded area, where bottle gentian thrives, bloomed little and have died off. If it is dry in summer, plants should be watered, along with the other garden plants. They do not need a swamp, bog, ditch or shade to grow well on your own small property.

Another point in reference materials is that cardinal flower is a short-lived perennial. And that is where I made my recent errors. I had observed that my plants increased in the number of flowering stalks and in their height each year for about eight or nine years. I mistakenly thought that they would keep on growing year to year, so I deadheaded plants to avoid too many new seedlings. I figured I had enough plants. However, the following spring of 2020, the cardinal flowers did not re-sprout. And I did not have seedlings coming up, due to deadheading plants the previous year. My hummingbird magnet had disappeared!

Starting from scratch again, I found about four seedlings in the lawn and transplanted them to garden beds. I also bought plants from the August 2020 RIWPS online sale and then some more in June 2021. To maintain these beautiful flowers, I’m going to leave seed on some plants to produce new seedlings. I’ll encourage some self-sown seedlings every year, in order to have a population of plants of various sizes and ages that will persist from year to year.

So, to summarize: full sun is fine, plant in good garden soil and irrigate as needed in summer; leave some seed on plants to produce some new seedlings each year; encourage lots of plants, and be happy when seedlings surprise you in new locations around your garden. Learn to recognize young seedlings, so that you can transplant them to other locations if you wish. In late summer the hummingbirds can’t keep away.


Just a Thought on Invasives

Living in Charlestown along Foster Cove, it can be overwhelming to know what from what, and I have discovered that I have lots of each! I have seen my neighbors hire landscapers to clear out “invasives” but they end up just clear-cutting everything. The invasives roar back saying “thanks for the trim!”

Growing Native Plants from Seed

This article by Dorothy Swift originally appeared in WildfloraRI, Spring 2018.

Why grow wild plants from seed?

Grow­ing plants from seed provides more plants for your property than buying larger, more costly plants from a com­mercial or nonprofit source. Certainly, either Lobelia cardinalis or Penstemon digitalis is lovely as a single plant, but most people want multiple cardinal flow­ers or groups of penstemon throughout a planted area.

When you grow plants from seed, you may be able to obtain seed of local origin for a species. Using locally-sourced seed is a sound ecologi­cal approach for establishing wild plants on your property and for including spe­cies that are not readily available com­mercially or are prohibitively expensive.

Finally, there is the challenge of doing something that might be difficult and the satisfaction of acquiring knowledge and experience in the propagation of native plants.

For a home gardener, how might this be different from growing vegetables and flowers from commercial seeds? Generally, commercially available vegetable and flower seeds germinate readily, whether you sow them in the ground, start them earlier under arti­ficial lights, or use natural light from a window. Many of these plants are annuals or are tender perennials treated as annuals horticulturally. Only a few native species respond with immedi­ate germination, as popular commercial vegetable and flower garden seeds do.

Most native species require a cold period before the seed will germinate. This is often referred to as “cold stratification,” a technique that exposes seeds to moist, cold conditions for a period of time. (The seeds must be in a moist medium, such as a seed-growing mix. Dry storage of seed in the refrigerator does not meet the need for cold, moist stratification.) A few species have even stricter requirements, such as a warm period followed by a cold period followed by a warm period. It can take up to a year or longer for some seeds to germinate. You must be prepared for a longer investment of time and nurturing when growing most native species from seeds.

How do you learn the best method for starting a native species from seed? There are several ready sources. For 30 years, every WildfloraRI issue has had a Cultivation Note which includes information about the best habitat for a species, how to propagate and grow the plant, and in most cases, how to grow the species from seed.

Our favorite source of advice in Seed Starters East is Willam Cullina’s book, Growing and Propagating Wildflow­ers. Cullina worked in the propagation and nursery operation at New England Wild Flower Society for many years and writes about his personal experi­ence propagating numerous native species. He explains their requirements for germination and provides advice on techniques to save time with some of the slower species. Though out of print, used copies of Cullina’s book are available from online services, such as Alibris.

Doing an online search can also be useful. Use the species name and “seed propagation” to find information, par­ticularly from various other native plant and conservation organizations. Your results will include a lot of sources, but for most species the first two listed are adequate.

If you have difficulty finding informa­tion on a species, you may want to use the work of Norman C. Deno, Seed Germination Theory and Practice, 2nd edition. Deno’s work concentrates entirely on germination, not on how to grow plants further. His presentation of information can be a bit difficult to understand, but the work encompasses hundreds of plant species. The entire work can be found online.

What are some of the basics of wild plants from seed?

1. After you collect and clean or pur­chase seed, refrigerate it if you are not going to sow it right away. I put envelopes of dried seed on a shelf of my refrigerator door for storage. Alternatively, put seed into small bottles or vials, together with a desiccant. (You can save the little packets of desiccants from commercial products, such as large bottles of pills). Do not store seed at room temperature

2. When you are starting out, use a seed starting mix rather than a general potting mix. Some plants germinate readily and grow vigorously, so potting mix can be suitable, but in general, a fine-textured mix formulated for starting seed works best. I use a mix from Gardener’s Supply Company. It is expensive but is free of weed seeds and contaminating microorganisms. Published instructions for some plants, such as lily species, may recommend milled sphagnum moss, which is also very finely textured. Al­ternatively, you can purchase sphagnum moss and rub it through a fine sieve or between your fingers to get fine particles. Also, carefully clean any used pots or containers to avoid bringing fungus pests to your seed-starting. You can run your pots or seed boxes through a dishwasher to remove disease organisms.

3. Carefully moisten the seed-starting mix. This is more critical for seed-starting than for transplanting. Proper wetting of the mix may require less water than you might think is correct. Moist, but not too much, is the key. To control moistening more easily, prepare a small volume of mix at a time. Then fill the seed-starting container, and settle the mix by rapping it against a hard surface.

4. Learn whether the seed should be covered or uncovered by the seed­ing mix. Several kinds of seeds, such as Lobelia cardinalis and Rhododendron species are small and need light, so spread them onto the surface of the mix. Avoid sowing the seeds heavily. You do not want the baby plants coming up like a lawn. For seeds that need to be covered, the depth should be approximately the diameter of the seed. Label the container with the species name and the date. Mist the container with water.

5. Maintain moisture after sowing. Enclose the seed container in a Ziploc bag or a takeout food container with a tight semi-transparent cover, especially if seeds are indoors under lights. If you rely on window lighting, never place the container of sown seed where direct sun shines on it. Check periodically that the container is still moist, and mist if neces­sary.

Many seeds, as mentioned, need a cold period after sowing. Put the container into your refrigerator or outdoors with protection from rodents. Outside, place plastic-covered containers under shrubs for shade, or cover larger seed flats with rigid metal hardware cloth or screening. Alternatively, you can use a cold place, such as an enclosed unheated breezeway, the stairs of a bulkhead entrance to a basement, or a cold frame. Light is not required during this cold period.

6. When germination begins, remove any plastic covering, and keep the mix moist by using a mist bottle or by setting the container in water so that moisture is absorbed from the bottom. If you must water from above, use a small watering can with a small-diameter spout that can dispense water very gently.

7. Do not transplant seedlings until they have a pair of true leaves, which emerge after the cotyledons or seed leaves. When transplanting, hold a seedling by a leaf to prevent damage to the stem. Seedlings don’t do well with too much space, so transplant several into a pot, or plant seedlings in rows in a takeout food container.

These suggestions should help you get started in growing native plants. Seed Starters East has sold seeds of several species this year. We selected ones that are likely to succeed if you fol­low simple directions. For species that need no special treatment, try Lobelia cardinalis, Penstemon digitalis, and Aquilegia canadensis. The milkweed species, Asclepias tuberosa and Ascle­pias incarnata are easy species but need a cold period.

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