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Are you planting tomato seed this year? I will teach you how I grow many varieties of tomatoes from seed in this article. Have you decided which tomato varieties you will be growing this year? There are so many varieties, I think that is the hardest part of planting tomato seed! Just trying to decide! When you are deciding, think about how you will use them. I like to make a lot of tomato sauce to can up and keep in the pantry and I also like to freeze a bunch. I also love to eat them fresh. And I love to try new varieties as well as stick with the old that have worked well for me or taste the best. Below I have listed out which cherry tomatoes, heirloom tomatoes and roma or paste tomatoes I will be growing this year. Breaking them down into these three categories makes it a wee bit less intimidating!
Past favorites that I have grown before and will grow again this year:
New varieties for this year will include more plain old red cherries. Last year, I didn’t grow a single red cherry tomato, so my goal was to find a new red one to add to the assortment. Below are the new varieties I am trying this year:
For the past few years, I have grown the same three paste tomato varieties, and I will planting them again this year. But I am excited to try a new variety this year!
OK, here is where I have trouble reining things in. Every year I tell myself that I have to plant fewer, but it just doesn’t happen. I currently have 10 old standbys on my list, and 9 new ones to try. Gulp. That makes 30 varieties of tomatoes total. Shhhhhhhhh……….don’t tell my husband!!! LOL!
Past favorites that I have grown before and will grow again this year:
New varieties for me this year:
If you haven’t checked out my Seed Starting 101: Essential Seed Starting Equipment post, I go over all the supplies I use and it may be helpful for you to review. I also plant my tomato seed exactly like I do my pepper seed, so reviewing that article Seed Starting 101: Planting Pepper Seed may also be helpful. And last, one of my most popular articles is Seed Starting 101: Winter Sowing. This article goes over how I use milk jugs as winter sowing containers, to start all kinds of seeds outside in the dead of winter. These containers act as little greenhouses and it’s really a fun inexpensive way to start seeds.
Planting tomato seed time frames will vary depending on your gardening zone. Most seed packets will tell you to plant tomato seed 6-8 weeks before the last frost. Here where I live, the last frost, is April 15th. But it is usually still too cold for the plants to go outside until around May 15th. This can factor in to when you plant your seed, especially if you do not have a lot of space indoors for your plant starts, or somewhere warm, like a greenhouse, for them to wait out those cold nights. Folks around here will start as early as February. I tend to wait until the middle of March because I grow so many. About a third to half of my starts get sold and I cannot afford to up pot them into a pot larger than 4″. If I start much earlier than the middle of March, the plants get too long and leggy for people to safely transport home in that little 4″ pot as most don’t want to take them home until around May 1st. So consider your frost date, and also consider when your night time temperatures get consistently above 50 degrees. These two dates can help you figure out the best time to start your seeds.
I use heat mats, along with six 6 cell seed starting packs in a growing tray with no drainage holes with a plastic dome cover lid. This allows me to start 36 plants in one tray. I use potting soil that I buy at Costco, the organic Miracle Grow Moisture Control Potting Soil and it comes in a 55 quart bag for $9.99. I put the soil in a 14 quart Rubbermaid Bin and add a bit of water to it, and stir it around well. You want the soil damp, but not drippy or soupy.
Fill all the cells with soil and tamp it down good in each cell with your fingers. I indent the soil about a 1/4″ with the fat end of a chopstick, or the eraser end of a pencil, lay down the seed inside the indent, than cover lightly with soil and press down again. It is very important that the seed be in contact with the soil completely around. I place 2 seeds in each cell if the seed is fresh and I feel confident in it. If it is older seed, or from a swap and I don’t know how old it is, I tend to use 3-4 seeds in each cell. Than I use a spray bottle and lightly spray the seed until I know that the seed and all surrounding soil is completely damp. If the seed floats up, just poke it back down under the soil. Than place a plastic dome lid on top of the tray (or you can use plastic wrap), place tray on heating mat and your seed is planted.
The next few days, you want to watch the tray. Make sure the soil doesn’t dry out. If it does, take off the lid and spray again with water and then put the lid back on. Once the majority of the seed in the tray has germinated, take of the lid and keep it off. It is only used to keep humidity in while germination takes place.
After germination and removing the plastic dome lid, place the tray under grow lights and keep it on a heat mat. You want the lights to be very close to the leaves, only about an 1″ above them. As the plant grows, you will need to move the light up, so it is best if you can hang the light from a chain using “S” hooks, because they grow quickly, and you will be moving the light up often. If the light is too high, or you don’t use a light and place your seedlings on a window sill, the plants will get long and leggy, which does not make for a healthy plant. It is also a good idea to keep an oscillating fan on the starts, to prevent fungus from growing in soil that is too damp, and it helps make stronger stems. If you don’t have an oscillating fan, move the fan frequently so that it blows from a different angle. At this point, it is also best to water from the bottom. Use a watering can that has a long spout, lift one seed pack up a little bit, and fill the tray about 1/2 way with water. I also like to add fish fertilizer to the water. I dilute it about half what the directions say. It is stinky though! So if you are smelling something foul in the house, it may be your seed starts! Just a warning!
When the second set of leaves starts to grow, is when I take out some tiny scissors, and thin out the starts. I select the strongest looking start in each cell to keep, and then nip any others in that cell down at the soil level. The strongest seedling is NOT always the tallest. You want a thick healthy looking stem more than anything. You can elect to try to salvage the extra’s, and repot them all, but I find that that are so fragile at this age, I am not willing to take the risk of losing them at this point. Tomatoes are so easily rooted, I prefer to wait until I begin pruning out the suckers, and root those in water, if I need more of a certain variety.
Very quickly your starts will need to be up potted to a minimum of a 4″ pot, or I also like to use Solo Cups that I have cut a couple drainage holes into. I prefer the Solo cups because they are a little deeper. When transplanting, pick off the bottom leaves of the tomato plant and bury it as deep as you can in the pot. It will send off new roots along the stem that is buried, making for a stronger plant. If you have the space, you can up pot to a larger pot, but if you have a lot like I do, I just don’t have the space to move them all into larger pots until it is closer to the time they will move outside. They will still need to be babied at this point, and kept in a warm space, and ideally, still under grow lights. But often times they are too tall to go under your seed starting set up, so you might need to revamp the light set up at this point. Or move them out into the greenhouse if you have one. Do not put them outside until temperatures are above 50 degrees.
As with all starts, it is very important to harden them off slowly before moving them outdoors full time. Hardening off means, slowly acclimating them to the conditions outdoors. If you just move them outside one day, they will go into shock, and may not recover. Wait until daytime temps are above 50 degrees, The first few days, keep them in a sheltered location, not too windy, not out where they might receive a down pour if it rains, and not where they might receive HOT afternoon sun. Only put them out for two hours or so the first day, increasing slowly by an hour or two each day. If it is still below 50 degrees at night, you will have to bring them in at night. See my other article, How to Transplant Tomato Seedlings for more information on final planting of your seedlings. Also, consider planting more tomatoes than you had planned, after reading my Benefits of Freezing Your Tomato Harvest article!Tamara