Tomato Seed Starting - Start your Seeds for Fall

Growing Tomatoes in the Fall?
Here are some simple steps to fresh sauce, salsa and soup


For die-hard tomato lovers, growing tomatoes from seeds is worth the extra time and effort, because you can select more varieties of tomatoes—and did you know there are over 10,000 kinds of tomatoes? You’ve probably only tried a few kinds, so think of the possibilities for sauce, soup, salsa, salad, and whatever else you and your family enjoy eating. If you page through a seed catalog, you’ll see hundreds of options—many more than you’ll find as seedlings. All you need is a warm, bright location for the germination of the seeds, and water, soluble fertilizer, covered containers for your seeds, and sterile potting mix. Remember, don’t use regular garden soil to start tomato seeds. 

It's still a good time to grow tomatoes for fall, so you can still have a bounty harvest of tomatoes. In fact, your fall harvest could be even better than your spring harvest. 

There are some things to consider before you begin, including the types of tomatoes that will do best at this time of year. 

  • Determinate tomatoes are ideal for fall because they mature early, before the tomato actually sets. That means the tomato has done most of its growing before you can see the bearing of the fruit. 
  • Indeterminate tomatoes, also known as vine tomatoes, grow best with stalks in the ground for more support. They grow taller than determinates, and they will bloom, ripen and bear fruit all at once through its growth process. 
  • Early tomatoes will set fruit in a shorter time, with tolerance for lower temperatures at night. They are generally ready for harvest within 60 days. 
  • Other great varieties of fall tomatoes include red cherry, red grape, yellow sun gold, and La Roma reds. 

Here's how to do it:

  • Your containers should be about two inches deep and have good drainage. (Think yogurt or other similar containers for this part, just put holes in the bottoms, and make sure they’re well cleaned.) Put them on a tray. 
  • Tomatoes grow best in temperatures under 90 degrees, so keep that in mind as you find a place to grow your seeds. 
  • Read your seed packet very carefully, as it contains critical information. It will tell you when to plant the seeds indoors, and when it’s time to transplant outdoors. Make sure you’ve noted the depth of planting, the temperature for germination, and the days it will take for the seeds to germinate. 
  • Insert plant markers that are marked with weather resistant marker to help you record your seeds’ variety and growth. 
  • Drop 2-3 tomato seeds into each container. They won’t all germinate, so dropping a few in will ensure you get a seedling. 
  • Add a layer of vermiculite, which helps cover seeds and prevents a buildup of algae over your seedlings. It’s light enough to allow seedlings to break through. 
  • Water with a gentle spray, then place the tray under a dome lid. That will create humidity, which encourages the seedlings to grow.
  • Place your tray of seed containers under a bright light. Lamp light or window light isn’t sufficient; you need something like LED tube lights, and they need to be over your seed containers so that they’re almost touching. As the sprouts break through, raise the lights. 
  • After your seeds have broken through, remove the dome lid. 

After your seeds have germinated, here’s what’s next:

  • That light needs to stay on up to 16 hours a day. 
  • Instead of spraying water, pour it into the bottom tray, and not too much. All the water should be absorbed within 12 hours. The containers should not sit in water. 
  • Add water soluble fertilizer at half strength once the seeds have broken through and you can see leaves. Tomatoes are heavy feeders and need plenty of light, water, and nutrients. Add fertilizer when you first plant, then at 30 days, then again at 60 days. 
  • When the seedlings are about 2-4 inches tall, you can transplant to a larger container. Expose them to outdoor conditions gradually, starting with a few hours in the sun, then returning to shade a full day. Increase the time in the sun by an hour each day.  When they are 6-8 inches tall, you can transplant to the garden. 

Some more tips for growing fall tomatoes:

  • Eggshells provide a great calcium source for your tomatoes. Just wash the shells, grind them into powder, and add to the soil. 
  • Tea leaves and coffee grounds add a nitrogen boost to your tomatoes. 
  • Fun fact:  Finely cut up pet or human hair adds keratin, which is a helpful nutrient, to your soil.
  • Pick your tomato when it’s half green and half pink, and let it ripen the rest of the way in your kitchen. 
  • Find out if your variety of tomato needs structural support or not. Some indeterminate plants need a cage or trellis to climb, other indeterminates might need a stalk. 

Your tomatoes should be able to grow and produce until the first frost. Planting in mid-August should bring you a bumper crop through the fall. So, the faster you get planting, the faster you can imagine yourself enjoying a full season of your favorite comfort foods—like, pizza and pasta with the best homemade sauce, salads with the best tomatoes, and chips with the best homemade salsa.