How to Grow Plants from Seed

Want to have hundreds of annuals, perennials, herbs, and houseplants but can’t afford the high cost of buying starter plants? Most indoor and outdoor plants are easy to grow from seed. The procedure differs depending on the type of plant you want to grow

Preparing a Seedbed

Many larger seeds for outdoor gardens can be planted directly in the ground, while tiny seeds and those that need extra time to reach maturity should be started indoors. For the outdoor garden bed, break up the soil, remove clay and rocks, amend it with soil additives as desired, and rake it smooth. Do not use peat moss on the surface, or it will wick the moisture away from the seedlings.

For indoor planting, use a special seed starting mix and a shallow container. These mixes are pulverized to provide the fine texture needed for tiny seeds. They are also sterilized to prevent damping-off disease, which will often kill your seedlings if you attempt to pot in untreated soil. Soak the mix until it has absorbed all the water it can hold, and drain off extra moisture.

Buying and Planting Seeds

Dr. H.G.Hessayon’s The Flower Expert recommends buying F1 hybrid seed whenever possible. Although it costs more, the quality of the plants is higher.

Read the instructions on the seed packet carefully and follow them closely. The general rule is that seeds should be planted to a depth of three times their diameter. Dust-like seeds should not be covered at all, but should be scattered on the surface of the soil mix by tapping them gently from a piece of white cardboard. Some seeds need to be refrigerated after planting, if started indoors, to simulate the chill they would receive if grown in their native climate. Others need to soaked in water for a few days. If you’re in doubt and don’t have the seed packet, Park’s Success with Seeds gives detailed information on starting different kinds of seeds.

When planting dust-like seed, encase the entire planting container in plastic until the first green shoots appear; then gradually expose the container to the air.

Caring for Seedlings

All seedlings need to be thinned after planting. Failure to do this will result in weak, spindly plants. The seed package will give directions on how to space the plants.

Seedlings grown indoors may need to be placed under fluorescent lights to provide enough light for good development. Failure to provide sufficient light is a common cause of indoor seedling failure.

Most seedlings should be kept moist, using a weak fertilizer solution with every feeding and then gradually dried out a bit as they grow to encourage good root development. Seedlings grown indoors need to be moved to individual pots. Use the smallest pots that will accommodate the root systems, and move up as necessary until they’re ready for their permanent home indoors or out.

Planting Seedlings Outdoors

Seedlings should be planted outdoors according to the recommendations on the packet. Some kinds of plants can be planted outdoors before the last frost date. Planting in the coolest weather the seedlings will tolerate gets them off to a better start than waiting until it’s hot, but tender plants must wait until soil is very warm.

To plant seedlings out, move them outdoors for a few hours at a time first, to harden them off. When they’ve been acclimated to outdoor conditions, they can be planted in the ground. Select a cool, cloudy day for your planting and firm soil gently around the baby plants. Water gently, using a hose diffuser to avoid dislodging the tender seedlings. Store leftover seed in a zipper bag in a cool, dry place.

Don’t limit yourself to the same old marigolds and nasturtiums. You’ll be astonished at how easy and rewarding it is to grow hundreds of dollars worth of annuals, perennials, and exotic tropical plants for the cost of a few packets of seed.