Starting Annual Flower Seeds Indoors

Spring Pansies. Morning view from the balcony.

How exciting it is to hold seeds in the palm of your hand. The anticipation and promise of summer encapsulated in a tiny seed. A seed that can become a lovely plant hoisting big, bold brightly-colored fragrant blooms!  But wait, first things first.

Sowing seeds for annual flowering plants is no different than starting vegetable garden seeds. There are 3 critical things that all seeds require to germinate.  Water, proper temperature, and oxygen. For annual flower seeds, the other important component is light or darkness, which we will discuss in a minute.  How the gardener provides these will decide how successful or unsuccessful a seed growing project will ultimately be.

Tools of the Trade

Subjective focus on single flower sprout in a black plastic grid of a peat moss seed starting tray

For proper and successful indoor annual flower seed starting, you must have similar “tools of the trade” that vegetable seed growers also use.

  • Proper Seed Starting Soil Mix like Jung’s Family Mix
  • Trays, cells, starter wafers, domes, and flats will also be needed. If you are just starting out, simplicity is most helpful. Look to our Basic Seed Starting Kit, which contains all of these necessary parts.
  • Seedling Heat Mat is also critical to maintaining proper and consistent soil temperature, like a cozy bed for your precious little ones. A simple heat mat greatly speeds up the process of seed germination and often makes the decided difference between success and disappointment.

Light vs Darkness

Blurred summer background with flowers calendula

To germinate well, all seeds need to have good seed-to-soil contact, but for annual flowering plants, some varieties prefer light, while others prefer dark in order to germinate well.  Geranium and Zinnia seeds prefer dark conditions, but Petunia, Impatiens, and Ageratum all prefer light for optimum germination.

Luckily, the directions on the seed packet will have this type of specific information for you. Always read the directions on the packet label for this type of critical germination information. It is good to recognize seeds are a miracle in and of themselves, so even if the lighting conditions are not completely perfect, but you have provided optimum moisture, soil temperature and they have oxygen, most seeds will still germinate.

Pelleted Seeds vs Regular Seeds

High quality seeds of exquisite petunia, flower in a texture form for your personal garden. Can be used by seed producers for create new beautiful packaging with seed on background.

Some tiny annual flower seeds will come as pelleted seeds. Seeds are coated with an inert clay-type substance which makes the seeds appear larger and makes them easier to handle. Varieties like Petunias, Gomphrena, Coleus, and Ageratums are some tiny-seed types that are commonly pelletized.

When sowing pelleted seeds there are two critical factors that must be adhered to – First, assure the pellet is firmly pressed into the soil surface, but not covered. Second, to germinate well, pelleted seeds should be kept slightly more moist than regular seeds. Remember it is water penetrating the seed coat that initiates the germination process. With pelleted seeds, the water must dissolve the clay-coat and then the seed coat. It works well when done correctly, but if not seeds never germinate.

We recommend any pelleted seeds be started in their own tray, to maintain the necessary slightly wetter conditions. Once they germinate, you can back off on the moisture and let the soil surface dry a bit more to keep seedlings happy. If seedlings stay too wet, damping off or rotting can occur.

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Begin with a Simple Seed

Begin with a simple seed. Learn and get to know what types of annual flowers you are working with. When entertaining friends, it is helpful to know the personalities of those on your guest list. It allows you to create an environment where all will be comfortable and happy. Annual flower seeds are no different. Some are quite easy. Some show up early, others make a more tardy entrance, making us wish just for an instant, that we had not even invited them. But if the right conditions are met, they will pop up when they are good and ready. We, in turn, ended up completely delighted that they did finally grace us with their presence.

Other Recommended Reading

Little white cup of espresso coffee, opened book, blue semi-transparent vase with purple lilac flowers on rustic wooden table in the garden at spring morning after sunrise or at evening before sunset

At Jung Seed Co, we strive to be your go-to guide for all your gardening needs. Our YouTube channel The Garden Doctor by Dick Zondag is where he provides gardening tips for all levels of gardeners. When you need reliable gardening advice, turn to the trusted experts at Jung.

If you are in the Wisconsin area, please visit us at one of our Jung Garden Center locations for all your gardening needs. Otherwise, you can browse our website. To receive info on new products, exclusive deals, and specials, be sure to sign up for our weekly email. Join our Facebook page, to discuss all things gardening!

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