In recent years, the Instant Pot has soared in popularity as a one-stop shop for pressure-cooking, sautéing, steaming and boiling. Its multi-uses have made it a useful appliance to easily prepare anything from rice to pot-roast. But one lesser-known function of this kitchen gadget is that it can serve as a reliable incubator for germinating garden seeds.
This can be particularly helpful if you want to speed up germination with warm-weather crops, such as tomatoes, melons, peppers and cucumbers, and you don’t want to buy a heating mat. It can also be a useful tool if you’re simply late to germinate your seeds or live in an area with a colder climate and a shorter growing season.
For those new to gardening, seed germination is the first process in growing food when a seed breaks out of its dormant stage and begins its development into a seedling. Seeds require a certain temperature and moisture to transition out of their dormant state. Most seeds germinate in an environment between 68°F and 86°F.
At its lowest “yogurt setting” at 91°F, the Instant Pot is able to provide a controlled, consistent greenhouse-like environment, producing germinated seeds in as little time as 24 hours to seven days. Given that the temperature of the water is on the higher side, this method is best for warmer-weather crops or those that prefer a temperature range from 76°F to 86°F. We don’t recommend using the Instant Pot for cool-weather crops, such as those in the brassica family.
If you’re unsure about what may be the ideal temperature for your seeds and it doesn’t say on your seed package, the University of California has compiled this helpful cheat sheet.
Want to give it a whirl? Follow our instructions below.
What you will need:
- Plastic Ziploc bag
- Paper towel
- Instant Pot
- Pie plate/casserole dish and lid (optional)
- Potting containers for germinated seeds
- Soil or potting mix
- For every four or five seeds you are using, you will need one sheet of paper towel. Soak your paper towel sheets to the point that the sheet feels damp but not sopping wet. If it is too wet, it can make your seeds susceptible to mold.
- Dump your seeds on the bottom half of each sheet. There should be an inch between each one so the roots have room to grow.
- Fold the top half of the damp paper towel sheet over your seeds and place it inside the Ziploc bag.
- Label your bags with a Sharpie.
- Pour a half-cup of water into the pot and place your strainer inside. The water not only ensures that the appliance has something to heat up once it is turned on but will help foster a warm, humid environment. Make sure to change the water in your strainer every two to three days to avoid bacteria from brewing.
- Turn your Instant Pot on the lowest temperature on the yogurt setting at 91°F. (This will be the water temperature). You will need to restart your Instant Pot on this setting every eight to 99 hours. This depends on the version of your appliance. The maximum amount of time it is set to run on this setting can vary.
- Place your bags into the strainer. You can stack them as high as you want. Cover your Instant Pot with your lid. This can be a casserole or other appliance lid if you don’t want to attach the Instant Pot lid. On the strainer, the seeds inside the bags will be contained in a temperature of 86°F. If you have seeds that thrive in slightly lower temperatures, you can take a glass or metal pie plate or casserole dish and place it over top of the strainer. Put your bags on top of the plate and cover it with a casserole dish lid. The extra plate provides an additional barrier from the water and takes about 10°F off the temperature.
- You should check on your seeds twice a day after about 24 hours. If your seeds have been recently purchased or have a softer coating, you may notice that they start to germinate within a full day. Other crops can take up to a week for the majority of seeds to germinate. You will know that they are ready to be removed and transplanted when the seeds have sprouted a tiny white root about an inch or two in length. As you check on your seeds, make sure your hands are clean and be mindful of mold. If you start to see white fuzz growing on your seeds or on your paper towel, you have mold. You can kill it in its early stages by spraying it with a mix of equal parts water and hydrogen peroxide.
- Remove your seeds from the bags once they have germinated. Take a sanitized pair of tweezers and use your tweezers to grab the seed body—not the root—when you transfer them to a container with soil. Removing and transplanting the seeds as soon as they are germinated can prevent roots from getting tangled or rotting inside the bags.
- Once you’ve transplanted your seeds, make sure you have dug a tiny hole in the soil in your pot or container. Place the seed with the root pointing down towards the soil. Bury only the white root part and keep what remains of the seed above the soil line. Then give it about a tablespoon of water.
Additional Care Tips:
After germination occurs, seedlings require about 12 to 16 hours of light each day. If you do not have access to sunlight for this amount of time, grow lights are a helpful tool. Your potting mix should also have good air flow to prevent damping off disease. University of Minnesota Extension explains how to identify, prevent and manage the disease here.
You will also need to “harden off” your seedlings for a few weeks before you move them outside. This essentially means gradually introducing your seedlings to outdoor-like conditions while they are indoors to ensure they transition well when it is time to plant them in the garden. The University of Maryland Extension provides a few tips on best practices here.