For the most part, seeds will germinate when they are ready if they are given the right conditions. However, you can speed up the process by germinating seeds on a paper towel, this is called pre-sprouting, or pre-germinating, seeds.
All you need is a paper towel or coffee filter, a container that seals, seeds, and water.
Benefits of Pre-sprouting Seeds
Although pre-sprouting seeds by germinating with paper towels adds an extra step to the seed starting process, here are several reasons to go ahead and do it.
- Tests old seed. Over time seeds loose their viability. Unfortunately, you can’t tell by looking at them which ones will sprout and which ones won’t. They have to be planted and allowed to germinate. By pre-sprouting the seeds, you can plant only the seeds that germinate and toss the ones that don’t.
- Saves money. When you pre-sprout seeds, there’s no need to toss old seed packets that still have seeds in them. You’ll know in just a day or two if the seeds are viable or if you need to buy more for this year’s crop.
- Saves space. Starting seeds in soil can take up a lot of space, especially since you’ll need to start more than you actually need to make up for seeds that don’t germinate. By pre-sprouting the seeds, you only need containers for the seeds that have germinated.
- Saves time. When starting seeds in soil it can take several days to several weeks for them to germinate. Most seeds can be pre-germinated in just a couple of days with this method. This is especially important when your season is short and every day counts.
Materials Needed
- Seeds – larger seeds work best for this but you can pre-sprout any seed. Try beans, chard, cilantro, cole crops, cucumbers, eggplant, melons, peas, peppers, spinach, squash, tomatoes.
- Paper towels or coffee filters – either one will work, you just need something that will stay moist.
- Container with a lid – plastic egg cartons or muffin containers work well for this. You could also use clam shell type containers that berries come in. If you don’t have any containers, zippered bags will work too. The container doesn’t have to be clear, but with a clear container you can easily see what’s going on with the seeds. If you don’t have any containers, you can use zip lock bags, just be sure not to wrap the seeds in the paper towel or the roots might grow into the towel.
- Labels and markers – You’ll need a way to label the seeds. If you’re using egg cartons or muffin containers you can put duct tape on each compartment to label what seed is in it. If you’re using clam shell containers that don’t have compartments, you can make a “map” on the lid. A permanent marker won’t wash away so that’s a good choice too.
- Containers for planting seeds – You’ll want to have the containers you’re going to plant the seeds in ready to go. When the seeds start to germinate they can go from ready to plant to “too late” very quickly.
How to Germinate Seeds on Paper Towels
- Line the container with damp paper towels or coffee filters – just a layer or two is enough. The paper towels just needs to be damp not soaking wet, you don’t want mold.
- Sprinkle seeds on the paper towel.
- Cover the container to create a greenhouse affect and keep the paper towels moist.
- Check the seeds daily. If the paper towels start to dry out, mist it with water. I’ve never had pre-sprouted seeds grow mold but it is something to look out for, especially if they’ve been in the container for more than a few days.
- As soon as you notice a root growing out of a seed, it will need to be planted. Be careful not to damage the root. Larger seeds can be picked up with your fingers but you may need to use something to pick up smaller seeds – a wooden coffee stirrer or popsicle stick works well for this.
- Plant the seeds in soil. To plant the seeds lay the seed on soil and cover with seed starting mix. The seeds need to be planted twice as deep as the seed is big. Most of the time the seeds will do better if planted into containers with seed starting mix to grow into seedlings. However, larger seeds such as beans, peas, or squash can be planted directly into the garden if weather permits.
- Keep seeds moist. The seeds still need to stay moist and warm while they finish germinating. If you notice that the soil is drying out, use a spray bottle to dampen the soil. Once the plants are large enough, they can be transplanted into the garden.
What Seeds to Germinate
To state the obvious, you’ll want to limit your seed pre-sprouting to seeds you’re ready to plant – either in the garden or indoors to grow as transplants.
I find that larger seeds such as peas, beans and squash do really well when germinated in paper towels. They’re roots are large and you can are less likely to get damaged by growing into the paper towel.
That being said, you can do small seeds, they’re just a little trickier to handle. Slow germinating seeds like peppers often benefit from using the paper towel method.
I would not try to pre-sprout and then plant root crops such as carrots, beets and radishes. Nor do I pre-sprout seeds for vegetables that usually have a bunch of seeds in the packet, such as lettuce and leeks.
Problems with Pre-Sprouting Seeds
Probably the biggest problem with pre-sprouting seeds is waiting too long to plant the sprouted seed in soil.
If you’ve sprouted the seeds using the paper towel method and wait to long, the roots will grow into the paper towel and will be damaged when you try to remove them. They should really be planted as soon as possible after the root appears.
As I said earlier, they can go from just right to too big very quickly.
Where to Find Seeds
You can use paper towels to germinate almost any seeds. I really like to use this method with seeds saved from my garden or seeds I’ve received from gardening friends.
If you’ve been gardening for a while, you probably have old seeds in your seed organizer and you’ve wondered if they will still germinate. Germinate them in a paper towel and find out before you order new seeds.
If you do need to order seeds, we really like MIGardener and these other heirloom seed sellers.
