One of my favorite gardening activities is getting a jump on warm-season vegetables, herbs and flowers by starting seeds indoors.

In fact, it is an annual tradition in my home with everyone putting in “orders” for their summer favorites: tomatoes, moon vines and peppers for Mom and Dad; basil for my husband; sunflowers for my son and niece; and black-eyed Susan vines for my sister’s mailbox.

By starting early, vigorously growing transplants can be planted into sun-warmed soil where they will hit the ground running.

The best part of the whole experience is when I discover tiny green seedlings happily peeking through the foggy lids of the mini-greenhouses in the laundry room.

The feeling of excitement and joy can really only be matched by the satisfaction I get when harvesting the fruit of those same seeds later in the summer.


Just like babies, seedlings are fragile and susceptible to disease. They need to be clean and warm to thrive. An ideal indoor location should be warm and have access to electricity and water. I use my laundry room, which receives sun from a west-facing window and heat from the dryer.

Nearly every gardener has faced the disappointment of new seedlings suddenly turning brown at the soil line and flopping over dead.

To avoid this condition, known as damping off, sow seeds in sterile seed-starting media. Damping off is caused by a collection of fungi and is exacerbated by heavy, wet soil and cool growing conditions.

Horticultural heat mats can be used under trays and mini-greenhouses to warm soil temperatures and promote root development. Be sure to follow the manufacturer’s recommendations for use.

For best results, choose a product labeled for seed starting such as a bagged peat-based growing media, or coir, a renewable product made of shredded coconut fibers. Coir is sold in blocks or plugs that expand when soaked in hot water to make a well-drained, fluffy seedbed.

To create a warm, moist environment for initial seed germination, I suggest using a mini tabletop greenhouse. This contraption is simply a tray to hold soil and seeds with a clear domed lid to keep heat and moisture in until germination occurs.

Frugal gardeners re-use clean containers such as clear soda bottles and deli or produce packages to create a greenhouse effect. When using recycled containers, be sure to sanitize and add drainage holes.

Water and fertilize

Once seeds sprout, remove the lid to increase airflow and reduce disease potential. I use a small fan on its lowest setting to circulate warm air around seedlings. Fertilize with a diluted water-soluble fertilizer in warm water. Drain excess water away quickly. Continue fertilizing with every other watering to encourage growth.

There are two basic methods of starting seeds indoors. The first involves broadcasting seeds over growing media, allowing them to sprout and develop their first set of true leaves. These seedlings are then gently lifted out and repotted into larger containers until they are transplanted outdoors. The second method is to start and grow the seedlings in the same container until they are moved to the garden.

To read more on each method, read the Clemson Extension Home and Garden Information Center factsheet “Starting Seeds Indoors” found at

Light needs

Once seedlings emerge, they need 16-18 hours of good quality light daily. In my experience, this is where most folks “fail to plan.”

Sunlight through a window is not strong enough to produce vigorous plants. Seedlings that use their energy to stretch toward light never develop into healthy transplants. Instead, use an adjustable light source that can be positioned inches from the top of seedlings and moved up as they grow.

Simple fluorescent ‘shop lights’ make excellent adjustable grow lights for seedlings. No need to purchase expensive grow light bulbs as you will be moving these plants outside in 6-8 weeks or less. Premade grow lights are available for purchase or conduct an Internet search for lots of practical do-it-yourself ideas.

There is still plenty of time to gather seeds and supplies for some indoor seed starting fun.


Most warm-season crops won’t be planted outside until mid- to late March, which means you have until at least mid-February to get a jump on your summer garden.

Clemson Extension in Orangeburg and Charleston counties will offer “Growing Terrific Tomatoes” where home gardeners will learn to grow the biggest, tastiest tomatoes on the block.

Join Agents Amy Dabbs and Morgan Judy for an in-depth look at growing healthy, flavorful tomatoes. Topics covered include soil preparation, recommended tomato varieties, disease and insect control plus staking and fertilizing. Participants will learn about our upcoming “One Terrific Tomato Contest” coming this July.

For details on offerings:

February 19 class in Charleston,

February 26 class in Orangeburg,

Amy L. Dabbs is the urban horticulture extension agent and Tri-County Master Gardener coordinator for the Clemson University Cooperative Extension. Send questions to