When to Remove a Propagator Lid? (Important Facts)

Propagator lids are great things, but do you know when to remove them?

In this article, you will find it out, and I’ll tell you what will happen if you remove them too early, or too late.

What’s the Role of a Propagator?

The role of a propagator is to help the seeds germinate faster in higher temperatures and keep them moist for longer.

Some seeds don’t need specific temperatures to germinate. They can either germinate at 68 °F (20 °C), or 55 °F (14 °C). However, there are certain seeds, like tomatoes or chilies, that demand heat to grow.

A propagator lets them grow in temperatures between 70-77 °F (21-25 °C). In lower temperatures, these seeds will fail to germinate.

Even if some seeds don’t need a propagator to germinate, it’s good to have it, because plants grow faster when the temperature is relatively high. If you’re looking for a good one, buy this one on Amazon, by clicking here. Additionally, a propagator lets the moist stay inside, so your plants are less likely to dry out.

When to Remove a Propagator Lid?

You should remove a propagator lid as soon as you see your plants have a second, or third set of leaves, and are easy to handle.

Not all of your seeds will grow in the same tempo. Some of them will be bigger, and some will be smaller. As a rule of thumb, removing a propagator lid when about 30% of your plants have 2 or 3 sets of leaves is a good time.

Even if some plants are smaller, or you can’t see them, because they’re under ground, they’ve already started germinating, so you can already remove the propagator lid. They will do just fine without a propagator lid.

If you’re really afraid of your plants, and your temperature at home at night might be too low, it’s advisable to pop a lid over the seedlings, but only at night.

Before you put the plants in the ground, wait a couple of days for smaller sprouts to grow at least 2 sets of leaves, without a propagator lid. Then, you can think of pricking out all of your plants.

Small plants adapt well to the ground, so don’t be afraid to put them in pots, even if they look small. If your ground is ready or the conditions are correct outside, you can put your plants in the pot and let them grow.

What Happens if You Remove Propagator Lid Too Early?

If you remove a propagator lid too early, you might kill your plant, or in the best-case scenario, you will stunt its growth, because of too low temperature.

It all depends on how big your seedlings are, and what plant it is. If you remove a propagator lid once all the seedlings are still under ground, you will stunt their growth, and you will have to wait longer to see the sprouts because the temperature will be lower.

However, if the temperature is too low, and you remove the propagator lid before your sprouts have 2 sets of leaves, you might kill your plants. In general, temperatures over 50 °F (10 °C) shouldn’t kill your plant.

Most plants will not die because of the lack of a propagator lid. However, if you grow sensitive seedlings, like tomatoes or chilies, you shouldn’t remove the propagator lid too early. If you intend to plant tomatoes in pots, here’s an article on how to do it the right way.

What Happens if You Remove Propagator Lid Too Late?

If you remove a propagator lid too late, it might cause your plants to soften, making them difficult to survive in colder temperatures.

Also, if your sprouts are covered with a propagator lid for too long, they are more likely to develop fungi, which ultimately can kill your plants. Some plants will also be leggy.

Removing a propagator lid isn’t hard, but doing it at the right time is the key. If you keep your plants covered for too long, it might affect their growth in the future, or even kill them, so it’s better to remove the propagator lid a bit too early than a bit too late.


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