Starting Tomato Seeds – Step by Step

how to grow tomatoes from seedTomatoes are one of the most popular garden plants, and no wonder. A fresh tomato bears almost no resemblance to store-bought tomatoes. A freshly grown tomato is juicy, not mealy. Flavorful, not bland. And they come in a rainbow of yellow, orange, purple, green, rosy pink, and brightest scarlet, not just monochromatic red.

You can find a good selection of  tomato plants at almost any nursery, but why not start your own? Growing your own tomatoes from seed is the best option if you are looking for something different like a specific heirloom plant or a foreign favorite. It’s really not too late to start tomato seeds, but you should start soon!


1. Most seed companies recommend starting your seeds 8 weeks before transplanting outside. Tomatoes can be planted outside after all danger of frost has passed, and the soil temperature has warmed up a bit.

2. Start seeds inside using a good seed starter mix (see my previous post 5 Tips for Growing Tomatoes for more information).  If you prefer an even easier approach, purchase a peat pot growing kit that includes a growing container and plastic dome. I personally don’t have much luck with peat pots, but maybe you will.

3. Plant 2 seeds per pot to increase your chances of having at least one of them germinate!

4. Provide light, heat and moisture. A great way to give your seeds a boost is to warm up the soil. You can purchase seed starter heating mats or use a heating pad, set on low. Water the plants and then provide continued moisture by covering with the dome or plastic bag (don’t cover the heating pad with plastic and keep it away from the water!).  Add light – an inexpensive fluorescent light is fine – 6-12 inches above the dome. The light can stay on 24 hours or be turned off each night.

The set up I find works best for me: I place on old towel on a table, and put the heating pad on the towel. The container with the seed starter and seeds goes on top of the heating pad. The dome covers the container. A light hovers over the dome.

5. Once the seeds have germinated (usually anywhere from 7-14 days), remove the dome or plastic bag and the heating pad. Lower the light so that it remains 6-12 inches above the seedlings.

6. When the seedlings have grown enough to have 2 sets of leaves, it is time to re-pot. Once again use good quality potting soil. The seedlings are very delicate at this point, and potting soil that includes large pieces of bark or other debris can easily cut your seedlings in half! I personally prefer Miracle Grow Potting Soil with fertilizer included. I have used several other, less expensive potting soils, but always have best results with Miracle Grow.

Re-pot seedlings in a deep, but not necessarily large, container. Plastic cups, recycled milk cartons, or extra plant pots all work fine. Make sure there is a hole in the bottom for excess water. Plant the seedlings in soil right up to the first set of leaves. This will encourage your tomato plant to establish good roots, leading to a stronger plant.

7. At this point, you can keep the seedlings on a windowsill. Be sure to turn them occasionally so the plants grow straight. You’ll want to keep the plants in another container (remember the watering hole – you don’t want a windowsill full of water!). Dish tubs from the Dollar Store work well for this, or you could buy plastic trays that go under house plants.

8. Keep the plants moist, but not soggy. How often you have to water will depend on the outside temperature, the inside temperature, and the potting soil you are using. After the seedlings are looking stronger (that first day they will be a little droopy), reduce the number of seedlings to just one in each container. Do this by cutting off the other seedling with scissors. I know, it’s hard to do, but there isn’t room in the container for more than one plant.

9. Harden off your tomato plants for a week or so before planting outside. To do this, place them outside, sheltered from the wind, for a few hours each day, building up to 24 hours.  Now it’s time to plant them in your garden.

10. Once again, we will plant the tomatoes deeply, digging a large enough hole so that the tomatoes are planted right up to their first leaves. This does two things, it helps the plants establish strong roots and it helps protect the plants from spring winds. Another good way to protect your plants is to cover them with row cover or a gardening blanket (I get mine here). Once the tomatoes are growing well, remove the cover, add mulch, and give the plants something for structure like a tomato cage.

11. Enjoy your freshly grown, downright delicious, tomatoes!

by Renee Pottle

Renee Pottle, a freelance writer and Home Economist, is fanatic about all things food. She blogs about canning and food preservation at Find her professional food writing info at

April 5, 2013

You May Also Like…

What to do with Leggy Tomato Seedlings

What to do with Leggy Tomato Seedlings

It seems to happen every year; my tomato seedlings bolt for the sky. Of course, this means I end up with tall, leggy seedlings. Leggy seedlings are less likely to grow into strong, producing plants.

Coffee Cup Herb Garden

Coffee Cup Herb Garden

Tame your overflowing coffee cup collection by turning it into an indoor herb garden.
Brighten up gray winter days by planting an indoor herb garden now.
Repurpose old, chipped or oversized mugs – turn them into a quick and easy indoor garden.

Best Gifts for Gardeners and Plant Lovers

Best Gifts for Gardeners and Plant Lovers

Find the perfect gift for the plant lovers on your list, without busting your budget.
Get your favorite gardener a magazine subscription or a new planner.
Growing kits and live plants are great gifts for gardeners, houseplant enthusiasts, and kids too!


Submit a Comment

Your email address will not be published. Required fields are marked *