Whether you have existing plants that you want to harvest from, or you know a good place to buy seeds, Aloe vera can be started by seed without much trouble.
Not all species of Aloe can be grown from seed, either because it won’t grow true or the leaves won’t germinate reliably. This guide is focused solely on Aloe vera, which can easily be grown by seed.
When purchasing seeds, look for a reliable retailer so you can be sure the seeds are fresh. Old seeds won’t germinate reliably. If you harvest the seeds from a plant you have access to, use them within a year.
Harvest Aloe Seeds
You can only harvest aloe seeds if your plant flowers. Most plants grown indoors won’t flower, though they might if you give them enough bright, direct sunlight. If you’re growing your plant indoors and you want to encourage it to flower, you can either move it outside after a period of hardening off or try to find a spot in your house with direct light for at least six hours.
You can also use supplemental lighting to increase your plant’s light exposure.
If it still doesn’t flower, try to expose it to 10 degrees higher temperatures during the day than at night.
It might take up to a year for your plant to flower. Be sure to bring it indoors if the temperature drops below 45°F.
After the plant flowers, allow the blossom to turn brown and hard. Don’t cut the spent flower off the plant. Once the seed pods develop, they will either fall off the plant, or they will start to split open. The pods should be dark and hard. If they are green or soft, they aren’t ready.
Once this happens, you can gently break the pods open using your fingernails or the blunt end of a butter knife, to expose the small gray or brown seeds. Any seeds that are pale or green aren’t mature and won’t germinate.
Remove the small seeds and gently rub off the white coating. Place the seeds on a tray, plate, or paper towel and allow them to fully dry. This might take a few days to a week.
You can store the seeds in an envelope or paper bag in a dark, cool area for up to a year.
Plant Aloe Seeds
Once you’re ready to plant, pull out your harvested seeds or purchase them from a reputable retailer.
Planting is best done in spring or summer if you live in the northern hemisphere so the plants have plenty of time to become established before the dormant season. While you can start the seeds directly outdoors if you want, it’s easier to start them indoors. When you grow indoors, you can better control the environment, including light and temperature.
Aloes are best started in a shallow seed tray or in individual four-inch pots. Fill the containers with succulent or cactus potting mix or a homemade mix made out of half sphagnum moss and sand. If you re-use pots or trays, be sure to wipe them out with soapy water or a 1:10 bleach-to-water mixture.
A loose, well-draining medium is crucial. Aloe plants can’t tolerate wet roots.
Moisten the medium so that it feels like a well-wrung-out sponge. You want to keep the soil about this moist at first, but never let it become wetter than this. A little bit of dryness is acceptable, but excess moisture isn’t.
Set the seeds an inch apart in the tray or place about three seeds per pot. Lightly cover the seeds. Spray the medium with a spray bottle to moisten it without disturbing the seeds.
Place the seeds on a heat mat or put them in an area that is consistently about 75°F (23°C). You want the trays or pots to be in bright, indirect light. While they can tolerate direct sun once they get older, young plants can’t direct sun when they’re young.
Don’t place a lid or plastic bag over the seeds. While some people might recommend this, aloe doesn’t need high humidity to germinate, and too much moisture will cause fungal issues and rot.
Spray the growing medium regularly to keep it moist to dry. Don’t let the soil dry out completely.
Seeds should germinate within about two to three weeks, though it might take up to a month. As the seedlings emerge, separate them, if necessary, so that they don’t crowd and touch each other.
If any seedlings start to turn yellow or brown, pull them and dispose of them.
Once they emerge, gradually start to expose the seedlings to more light. Do this in 30-minute increments, meaning that you should place the seeds in direct light for about 30 minutes and then put it back in its original spot. The next day, expose it to direct light for an hour before moving it back to its regular spot. Each day, add another 30 minutes until the seedlings can be in about four-six hours of light.
Once the leaves are about six inches long, you can move the plant to its permanent pot or spot outdoors. Reduce the amount of water you give the plants, allowing the soil to dry out for a bit between watering.