Germination Chart For Annual Flowering Plants

Germination requirements (light and temperature) vary among the different flowers and vegetables. The various crops also differ in the length of time from seed sowing until the seedlings are transplanted outdoors.

The following chart provides germination information for many of the commonly grown annual flowers.

Annual Germination
Temperature
(Fahrenheit)
Lighting Days to
Germination
Weeks Sowing
to Planting
Ageratum (Ageratum houstonianum) 70-75 L 7-10 8
Snapdragon (Antirrhinum majus) 70 L 7-14 8-10
Wax Begonia (Begonia x semperflorens-cultorum) 70-75 L 14 10-12
Annual Aster (Callistephus chinensis) 70 L-D 7-10 6-8
Vinca (Cathranthus roseus) 70-75 L-D 14 10
Cockscomb (Cleosia spp.) 70-75 D 7-10 6-7
Bachelor's Button (Centaurea cyanus) 65-70 L-D 7-14 8
Cosmos (Cosmos spp.) 70 D 5-7 4-6
Lisianthus (Eustoma grandiflorum) 75 L 10-14 14
Globe Amaranth (Gomphrena globosa) 70 L-D 14 7-8
Sunflower* (Helianthus annuus) 70 D 5-7 3-4
Strawflower (Helichrysum bracteatum) 70-75 L-D 7-10 6-8
Impatiens (Impatiens wallerana) 70-75 L 10-14 8-10
Annual Statice (Limonium sinuatum) 70 L-D 7-10 8-10
Melampodium (Melampodium paludosum) 65-70 L-D 7-10 7
Four-O'Clock (Mirabilis jalapa) 70 D 5-7 6-8
Flowering Tobacco (Nicotiana alata) 70-75 L 10-14 8
Geranium (Pelargonium x hortorum) 70-75 D 7-21 12
Petunia (Petunia x hybrida) 75 L 7-10 8-10
Moss Rose (Portulaca grandiflora) 75 L 7-10 10
Black-Eyed Susan (Rudbeckia spp.) 70 L-D 7-14 10
Red Salvia (Salvia splendens) 70-75 L 10-14 8
Mealycup Sage (Salvia farinacea) 70-75 L 10-14 8-9
Creeping Zinnia (Sanvitalia procumbens) 70 D 7-10 6-7
Coleus (Solenostemon spp.) 70-75 L 10-14 8-10
Dahlberg Daisy (Thymophylla tenuiloba) 65-70 L 14 8
Nasturtium* (Tropaeolum majus) 65-70 D 10-14 5-6
Zinnia (Zinnia elegans) 70 D 5-7 5

*Sunflowers and nasturtiums do not transplant well. Both should be seeded directly into peat pots.

Light conditions during germination are critical for many annual flowers. The seeds of some plant species require light for germination. (In the table above, annuals that require light for germination are designated with the letter L in the lighting column.) After sowing these seeds, lightly press them into the germination medium, but do not cover them. The seeds of other flowers require darkness (D) and should be covered with the germination medium. Finally, those designated L-D should be lightly covered, leaving the seeds as close to the soil surface as possible.

Category: Horticulture
Authors: Richard Jauron
Iowa State University

Links to this article are strongly encouraged, and this article may be republished without further permission if published as written and if credit is given to the author, Horticulture and Home Pest News, and Iowa State University Extension and Outreach.

Garden Vegetable Germination Chart

Vegetable Germination Chart

6 responses to “Germination Chart For Annual Flowering Plants

  1. I prefer perennials. I’ve been looking at the County Extension plant sales today. Here in the Great Lakes they sell beach grass…which pleases me no end.

    Like

  2. 60F and sunny on the Equinox yesterday. Tempting to start planting, but March is too early for our mountains. Restrain, restraint, restraint. We have the seeds lined up and ready to go. For now, cutting and splitting next year’s wood, cleaning out the garden beds, and enjoy the daffodils, snow drops, etc. are our pleasure. – Oscar

    Liked by 1 person

  3. Thank you very informative 🙂

    Like

  4. Not much germinating here yet! Can’t wait though (but I guess I’ll have to).

    Like

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s