Heading to the local nursery for a six-pack of tomato plants is fine for most gardeners. But that won't do for the legions of home growers obsessed with raising America's favorite garden vegetable from seed.

	Doug's favorite tomatoes (in no particular order): Potato Top Sungold Cherokee Purple Eva Purple Ball Brandy Boy Fourth of July Super Bush Container Choice Lucky Leprechaun Hillbilly Supersonic Super Italian Paste Stupice More gardening news Garden Notes: Gardening workshops, shows herald spring

Many do it because they know the plants will produce earlier and be healthier. But starting from seed also opens the door to thousands of fascinating varieties you won't find at the nursery.

Last year, I tried Burpee's 'Brandy Boy,' a hybrid derived from heirloom superstar 'Brandywine.' It bragged of old-fashioned taste and modern productivity. Guess what? It lived up to every claim and made it onto my must-grow list. This year, I'll also be giving Park Seed's 'Razzelberry' a try. It's a pink tomato that won the company's taste test.

Tomatoes are one of the easiest plants to grow from seed. I start my early varieties the third week of March and main crop on the first of April.

The first priority is light. A large south-facing window might work, but fluorescent shop lights hung just an inch above the plants are ideal.

Use a soil-less mix designed for seed starting, not potting soil. Wet the mix first so it's moist but not dripping, then fill the container.

Place the seed on the mix and cover with a little more of the medium. Press down to assure good contact between the seed and mix. Cover the container with clear plastic and place it under the lights.

In a week or so, the plants will sprout. When they grow their second set of leaves, start fertilizing at half strength and gradually increase the concentration through the next month, fertilizing once a week.

As the plants grow, keep potting them up in bigger containers. The tomatoes will love it. Those early varieties started in March will eventually end up in 10- to 12-inch pots, staked and loaded with small green fruit. Many will be ready to pick in late June.

Before planting seedlings in the garden, give them time to adjust to the outdoors. Called hardening off, the process begins with just a few hours outdoors in a protected spot. Gradually increase the time until, at the end of the week, the plants are out all day.

I've seen tomatoes thrive that were planted outdoors as early as April, but I've also seen some planted in mid-May cut down by frost. In our climate, wait until the end of May after all chance of frost has passed. Tomatoes love it hot. When they're planted in cool wet weather, they just sit there until things warm up, so what's the hurry?

Give your tomatoes a good home by improving the soil. Work in organic matter like mushroom manure or good compost. Add a couple tablespoons of Epsom salts to each planting hole. This helps the plant form a strong root system.

Bury the plant as deep as possible; roots will form along the underground stem. Most tomatoes need staking, but I cage most of mine. I use concrete reinforcing wire cut into 5-foot lengths to form the cage.

Last season was a tough one for tomato growers. Many plants succumbed to fungal diseases that thrive in cool, rainy conditions. To avoid the same problems this year, plant seedlings at least 3 feet apart.

When the soil warms up in June, a thick layer of mulch is beneficial. It will stop fungal spores from splashing up on the leaves and keep the plants consistently moist during the summer, warding off blossom end rot.

Fungicide is a last resort. For best results, be proactive: Treat your plants before they show signs of disease. A homemade organic recipe works well. Mix a tablespoon each of baking soda, vegetable oil and dishwashing soap into a gallon of water. Before using the mixture on the whole plant, put a little on one leaf to be sure it doesn't burn. Spray it on the plant in the morning, and don't forget the undersides of leaves.

Growing tomatoes from seed offers many rewards. One of the best might be bragging rights in the neighborhood. Trying to produce the first, biggest or tastiest tomato on the block is a good-natured tradition gardeners have carried on for decades.

'Potato Top' seeds

For the past five years, I've offered free seeds for the Pittsburgh heirloom tomato 'Potato Top.' A tradition in Fred Limbaugh's family, it gets its name from its potato-like foliage. It produces a large (up to 2 pounds) pink tomato with few seeds and a great old-fashioned taste. Each year, I send 'Potato Top' seeds to readers. All I ask is that they send back seeds from the first tomato so we can keep this great variety alive. Last year, I received more than 140,000 seeds in return. I stuff all the envelopes with the help of the Penn Hebron Garden Club.

If you would like to try 'Potato Top', send a business-sized (9 1/2-by-4 1/2-inch), self -addressed, stamped envelope to: Doug Oster, The Backyard Gardener, Pittsburgh Post-Gazette, 34 Blvd. Of the Allies, Pittsburgh PA 15222.

The tomato is a late variety, so be sure to grow something that will give you some tomatoes earlier.