Here are some suggestions for starting seeds.
Guidelines for Starting Seedlings
1. The general rule is that seeds should have a sterile pot and potting mix with no fertilizer. Potting mixes prevent soil compaction and are free of insects, disease and weed seeds. A soil that is fine outside where nature can keep these pests at bay, would put your seedlings at risk of problems like damping off and cut worms, and compact soil makes it difficult for tender new roots to develop.
At the greenhouse, we use Promix which is a mixture of sphagnum moss, perlite, vermiculite, dolomite lime (to stabilize the pH) and a wetting agent for even water absorption.
Spagnum moss is well draining yet water retentive.Perlite looks like styrofoam but is a volcanic mineral. It aids in air and water retention.
Vermiculite is a mica-type material that is heated and expanded. It holds water and nutrients until the plants are ready to use them.
Dolomite lime sweetens the mix which is naturally acidic.
The wetting agent makes it easier to wet the mix.
2. The potting mix should thoroughly damp but not soggy before using. If the soil is not wet place the tray on a soaker tray until the surface just begins to show the wetness. Don't let the mix get too wet or the seeds could rot.
3. Fill 6 packs with mix and gently tamp it down. About ¼ inch from top is good. Put one seed in each compartment. Read the package for the seed depth. 1/8 to ¼ inch is typical depending on the size of the seed. Larger seeds are planted deeper, for example, beans are planted 2” deep. Some seeds need light to germinate and should be placed on the soil, others need darkness to germinate and are planted deeper.
4. Label each 6 pack with specific name, and date planted. Flower seeds should be marked with height. Zinnias and marigolds, for example, come in cut flower and border heights.
5. Place seedling in a germination bed or on a heat mat or other warm place. It is important to read germination temperature. Some seeds germinate at cooler temperatures. Most vegetable like to germinate at about 75, but some flowers need lower temperatures.
6. Most seeds need to be kept moist to germinate. Check seeds in the germination bed to make sure the soil is damp and sand under the flat is also damp. Soggy soil can rot the seeds so it is important not to over-water.
6. Seeds in the germination bed have a humid environment because of the plastic cover. You can also do this with a plastic dome. It is a good idea to remove the plastic for a short time everyday to give the plants fresh air.
Betsy brought us a recipe to try with all the kale at the greenhouse.