Tomato seeds typically take five to seven days to sprout. The germinated seeds produce a thin stem with two leaves on top. You can speed up the germination process by putting the seeds in a damp paper towel. Light does not matter when germinating tomato seeds—only temperature and moisture levels come into play. Seeds may not sprout if they get too cold, dry out, or have been sitting around too long. If that happens, you just have to try again with new seeds.
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What Do Tomato Seeds Look Like When They Germinate?
A thin stem emerges first when tomato seeds germinate. Two leaves clasp together at the top. Then, the leaves separate to create a ‘T’ shape along with the stem. The initial seed leaves do not look anything like the true leaves of tomato plants. Instead, they are small, pointed ovals.
- A thin stem appears first as the tomato seeds fully germinate.
- Two leaves clasp together at the top of the initial stem growth.
- The pointed oval leaves separate as the plant starts to grow.
- True leaves form in the next week after sprouting.
The sprouts come up within five to seven days. The first set of true leaves will form in the following week. Then, the plant will branch out and grow many sets of its regular leaves.
Can You Speed Up the Tomato Seed Germination Time?
Germinate your tomato seeds faster by putting them in damp paper towels. Take a paper towel and fold it together lengthwise. Then, lightly dampen the entire surface with room temperature water. Spread out the seeds on one side of the paper towel and fold the other side over them. Put the paper towel in an open zip-top bag.
- Germinating your seeds in paper towels will help them sprout in less than 5 days.
- Fold a paper towel in half, dampen it with warm water, and spread out the seeds inside.
- Then, fold the paper towel over the seeds and put it in an open zip-top bag.
- Keep the seeds in an area that stays 70–80°F (21–26°C), like on top of the fridge.
- Check the paper towel daily to keep it moist until the seeds can sprout.
Keep the seeds on top of the fridge or in the cupboard beneath the kitchen sink. The area should stay in the 70–80°F (21–26°C) range. Check the paper towel daily to keep it moist. The seeds should sprout in less than five days.
Do Tomato Seeds Need Darkness to Germinate?
Tomato seeds do not need darkness to germinate. Light does not matter either. The seeds just need to stay moist and at the right temperature. The 70– 80°F (21–26°C) range is ideal.
- Tomato seeds do not need darkness to properly germinate.
- Light does not have any impact on how well the seeds germinate either.
- You just need to keep your seeds moist and at 70–80°F (21–26°C).
- Use this seedling heat mat to keep seeds planted in soil warm enough to sprout.
- If using the paper towel method, put your seeds on the fridge or under the sink cabinet.
If planting in soil, keep your seeds warm by putting the pots on a seedling heat mat. Place the seeds on the fridge or in the cabinet under the kitchen sink if using the paper towel method.
Why Won’t Your Tomato Seeds Sprout?
Tomato seeds refuse to sprout if they are too old, dry out, or sit outside the ideal temperature range. Only plant seeds that are less than four years old for the best germination rates. The seeds need moisture to break down the seed coating and nourish their initial stem growth.
- Tomato seeds may not sprout if they’re too old, have dried out, or don’t have enough warmth.
- For the best germination rates, plant seeds that are less than 4 years old.
- Tomato seeds need moisture to break down the seed coating and nourish the initial growth.
Tomato seeds need to stay in the 70–80°F (21–6°C) range to germinate in five to seven days. The seeds may sprout eventually at lower temperatures. At 50°F (10°C), for example, it takes tomato seeds 40 days to germinate. Oftentimes, the cold seeds won’t sprout at all.
What to Do if Your Tomato Seeds Don’t Sprout?
If your tomato seeds don’t sprout, just start again. Begin by trying to figure out why the seeds did not sprout. Were your seeds too old? Get new ones. Did the soil dry out? Water more often. Is it not warm enough? Add a heat mat or move your seeds to a new location.
- Plant new tomato seeds if the first batch did not sprout.
- Before replanting, try to figure out what went wrong.
- Aim to resolve the problem, so your new seeds germinate.
- Get starter plants from a nursery if it’s too late to plant new seeds.
Plant your new tomato seeds using what you learned from the first batch. Then, do all you can to help them thrive. If it’s too late in the season to start new seeds, get starter plants from your local nursery instead.
How Long Until Tomato Seeds Germinate?
When germinating tomato seeds, keep the following facts in mind:
- Tomato seeds germinate in 5–7 days.
- You must keep the seeds warm and moist to help them sprout.
- Light exposure does not impact seed germination rates in any way.
- Seeds do not germinate if they dry out, are too old, or don’t get enough warmth.
- You must plant new seeds if your initial batch fails to sprout.
Tomatoes are worth all the effort to sprout from seed and tend to all season long. Their ripe fruit boasts bold flavor unmatched by supermarket offerings. So, put your all into growing tomatoes, and then reap the rewards as the fresh fruit ripens.