How to Plant a Tomato Seed

Every season as summer draws near, thousands flood into nurseries and garden centers all across the states in search of tomato plants. The majority will be completely happy filling their gardens with store bought plants. For those who aren't , I dare to ask, "why aren't you satisfied?" Is it the lack of variety? How about stunted or spindly plants that may have been planted too early? Whatever the reason may be, turning to seed is a great way to solve your store bought woes. To keep you on the right track, this article will discuss everything you need to know about how to plant a tomato seed. When to plant, how to plant, and even tomato seedling care, you'll find it all right here!


When to Start Tomato Seeds - 
Learning the proper time frame to start you tomato seeds is by far the most important aspect of care for tomato plants. Plant too early and you'll risk stunted pants that begin to flower before they're even planted outdoors. Plant too late and you may never see the vigor or true potential of growth your plants have to offer. So, when to start tomatoes from seed? The answer is 5-8 weeks before the average last frost in your area. Tomato seeds started within this time frame will be large enough as young plants to quickly grab root in your garden, but will still have not begun to flower.


How to Plant Tomato Seed - 
Once you know when to plant, it's time to move onto how to plant! Below you'll find a list of basic supplies needed, directions for planting, and tips for successful seed germination. 

Yellow Grape Tomato Seeds. 
  • Tomato Seeds - Ah, the fun part! There are so many different tomato varieties that one can grow in their garden. For best results, I encourage you to seek out local seed producers with seeds already acclimated to your climate!
  • Containers - The number of containers will depend on the number of tomato plants that you plan to grow (one per container of course!).  For quick seedling growth, start tomato seeds in a three to four inch container. 
  • Sunlight/Artificial Light - Though light is not necessary until after the seeds have sprouted, it's very important to secure a source of lighting before the seeds are planted. Immediately after the seeds have germinated, the tender seedlings will require a great deal of light. To meet these needs, place tomatoes in a well-lit south facing windowsill, or under artificial grow lighting. 
  • Potting Soil/Seed Starter - You'll need some sort of growing medium to plant your seeds into. While some will choose to use a seed specific starter soil to plant into, I've always just planted directly into organic potting soil. It's really up to you. 

Directions for Planting - 
Zapotec Ribbed Heirloom
Tomato Seedlings.
(Nine Days Old)
  1. Fill each container with the potting soil or seed starter of your choice. Gently pack down the soil with your fingers and water in well. Allow the containers to drain completely before moving on. 
  2. Poke a hole in soil about a half inch deep. Plant one tomato seed per hole, and once again, one tomato seed per container. If you're worried about your tomato seeds not germinating, plant two per container and thin to one after they've sprouted. 
  3. Place the tomato seeds in a warm and dark place until they've sprouted. The top of the refrigerator is often a prime choice for this job. Loosely covering the tops of the containers with plastic wrap will hold in a bit of heat and humidity, further benefiting germination. 
  4. Once the seeds have begun to sprout, immediately move them to a well lit area!

Tomato Seedling Care - 
Zapotec Ribbed Heirloom
Tomato Seedlings.
(Twelve days old)
  1. The first task in caring for tomato seedlings is that you give them light. A south facing windowsill receiving full sun throughout the day will be plenty for tomato seedlings. If this cannot be provided, plan to use artificial lighting. Since grow lights cannot provide the same intensity the sun does, they must be run for longer periods of time to sustain tomato seedling growth. I've found that 16-18 hours under light in the 6700°K spectrum to be sufficient. 
  2. The second and final aspect of tomato seedling care is to provide adequate water. The young tomato plants will prefer that the soil be moist, but never waterlogged. To provide proper moisture, water the seedlings thoroughly only once the top inch of soil has become dry. Always allow excess water to drain away. Do not allow seedlings to sit in pools of standing water!

Tips for Success - 
  • Heirloom or Open Pollinated Seed - If you're looking to pluck some tomato seeds from a store bought tomato, think again! A lot of tomatoes found in stores have hybrid genetics and may have been chemically treated and/or grown. Not the best way to start your garden! For the best results, search for heirloom or open pollinated seed from reputable seed sources. If you must grow tomatoes from store bought specimens, only go with heirloom varieties, as these are open pollinated. (Even certified organic tomatoes for sale may have originated from hybrid seed.)
Tomato seedlings under
artificial lighting. 
  • Artificial Lighting - As I've mentioned before, the best spectrum of lighting for vegetative growth in tomato seedlings is 6700°K. For the actual light fixture, I recommend having at least 100 watts or lighting capable of producing 10,000 lumens for proper growth.
  • Proper Environment - For best results, place the tomato seedlings in an area indoors where the temperature remains stable and where there is plenty of air circulation. If the air does not circulate as desired, place a small fan next to the tomato plants.  It is also critical that temperatures remain above 65°F while growing indoors. Temperatures below this can stunt growth. 

Tomato seedling care is where we'll leave off at in this article. What comes next is even more fun! Transplanting your tomatoes to the great outdoors and caring for them as they begin to produce a bountiful harvest! Please be sure to tune in, as these guides will be released soon. Until then, thank you for reading this guide on how to plant a tomato seed! As always, please leave any comments or questions you may have.