© Sarah Pietrkiewicz A Monarch butterfly (Danaus plexippus) enjoying some goldenrod, in Toronto, Canada

Seed Bar Germination Instructions

Seeds of certain species need other special treatments in order to germinate. See more details, listed by species, below.

CN Tower re:grow Seed Bar Germination Instructions

The life cycles of native plants are tuned in to the seasons. Most native plants drop their seeds in the fall, but don’t germinate (“wake up”) until the warmer and sunnier days in the spring. The best way to grow these seeds is by working with those natural cycles, so, it’s best to sow seeds outdoors in the fall and just let them do their thing!

If you can’t wait until fall or you missed your window, there’s a trick you can do indoors called “cold moist stratification”; it only takes a few household materials and some patience. Place the seeds between moist paper towels or in vermiculite (a granular mineral compound that holds water and is available where garden supplies are sold), in a sealed bag or container, and store it in the fridge. Label the container with the species name and the date. Then, leave it in the fridge. The amount of refrigeration time needed varies depending on the species but is usually between 30 and 90 days. Check out this website to find out how much time is needed for the species you want to grow. Once that time has passed, remove the seeds from the fridge and sow.

Seeds of certain species need other special treatments in order to germinate. See more details by species below.

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A loose cluster of trumpet-shaped flowers on a tall, think stalk growing among tall grass.

Hairy Beardtongue
(Penstemon hirsutus)

Germination: For best results, sow on the soil surface in the fall. If germinating at a different time of year, place seeds between moist paper towels or in vermiculite, in a sealed bag or container, in the fridge (4 degrees C) for 60 days, then sow on the soil surface.

Habitat selection: sunny and rocky areas (good for containers)

Photo: © jallaj / Source: inaturalist.org

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Spikes of small purple flowers growing in a field.

Blue Vervain
(Verbena hastata)

Germination: For best results, sow on the soil surface in the fall. If germinating at a different time of year, place seeds between moist paper towels or in vermiculite, in a sealed bag or container, in the fridge (4 degrees C) for 30 days, then sow on the soil surface.

Habitat selection: sunny and wet area (good for containers with consistent watering)

Photo: © monoceba / Source: inaturalist.org

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Yellow upwards-pointing bell-shaped flowers.

Common Evening Primrose
(Oenothera biennis)

Germination: For best results, sow on the soil surface in the spring or late fall

Habitat selection: anywhere with at least a few hours of sunlight and some moisture.

Photo: © Alexey P. Seregin / Source: inaturalist.org

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Close up of tall cylindrical fuzzy purple flowers.

Dense Blazing Star
(Liatris spicata)

Germination: For best results, sow on the soil surface in the fall. If germinating at a different time of year, place seeds between moist paper towels or in vermiculite, in a sealed bag or container, in the fridge (4 degrees C) for 60 days, then sow on the soil surface.

Habitat selection: sunny and dry areas

Photo: © David Winston / Source: inaturalist.org

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© Nancy L Barrett

Black-eyed Susan
(Rudbeckia hirta)

Germination: For best results, sow on the soil surface in the fall. If germinating at a different time of year, place seeds between moist paper towels or in vermiculite, in a sealed bag or container, in the fridge (4 degrees C) for 30 days, then sow on the soil surface.

Habitat selection: sunny and dry areas

Learn More
© Howard Williams

Virginia Mountain Mint
(Pycnanthemum virginianum)

Germination: For best results, sow on the soil surface in the spring or late fall. Seeds are very small and need light to germinate. Make sure they are not covered by soil, leaves or other debris, especially when the weather begins to warm.

Habitat selection: sunny or partially sunny areas with medium to high moisture

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© alcastro28

Upland White Goldenrod
(Solidago ptarmicoides)

Germination: For best results, sow on the soil surface in the spring or late fall.

Habitat selection: sunny, rocky/gravelly areas, medium to low moisture

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© franz_herpman

Dotted Horsemint
(Monarda punctata)

Germination: For best results, sow on the soil surface in the spring or late fall.

Habitat selection: sunny, sandy areas with medium to low moisture

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© Jeremy Collison

Tall Thimbleweed
(Anemone virganiana)

Germination: For best results, sow on the soil surface in the fall. If germinating at a different time of year, place seeds between moist paper towels or in vermiculite, in a sealed bag or container, in the fridge (4 degrees C) for 60 days, then sow on the soil surface.

Habitat selection: sunny to partially sunny areas with somewhat dry to somewhat moist soil (quite adaptable), can grow well in clay soil

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© alcastro28

Smooth Aster
(Symphyotrichum laeve)

Germination: For best results, sow on the soil surface in the spring or late fall.

Habitat selection: sunny and moist to wet areas, can grow well in clay soil

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General Notes

All of these types of seeds can still germinate after being stored in a dark, cool and dry place for several years. However, the number of individual seeds that will germinate decreases each year that they’re kept in storage, so it’s best to use them within 12 months.

The germination instructions will help increase the number of seedlings that germinate and will improve the health of the plants, but even if you don’t follow the instructions precisely or just toss them on the soil somewhere, some will likely germinate.