How to Grow Rare Succulents and Cacti from Seeds
Growing cacti and succulents from seed is relatively straightforward, and can produce a diverse collection of plants in only a few years. There are more than 2,000 species of cacti and succulents suitable as tabletop potted plants or tall floor plants. Cactus and succulent seeds are generally available from commercial seed companies.
Clean propagation pans by washing them with disinfectant. Pans should be small and shallow, no more than 4 inches deep and 6 inches in diameter. There are many different suggested growing media formulas to experiment with. One formula calls for mixing a coarsely sifted organic growing medium, such as commercial potting soil, with an equal volume of sharp sand, perlite or pumice for drainage.
Pasteurize your growing medium by baking it in an oven at 300 degrees Fahrenheit for 30 minutes. Allow it to cool and wet it thoroughly. Let it drain but not dry out. Fill the propagation pans with the moist soil mixture to about ½ inch below the rim.
Sow seeds in the pans around the end of April. Plant seeds as deep into the soil as the seeds are wide and press down lightly. Cover small seeds with a sprinkling of sand to hold them in place. Seed spacing will depend on the species of cactus or succulent you are germinating. Cover the pans with clear plastic or glass. Place them in a bright location but out of direct sun. Keep temperature around 70 degrees Fahrenheit. If soil seems too dry, spray lightly with water. Be sparing. Too much water can drown the seed. Don’t let soil dry out.
Watch for germination. Most cacti and succulents will germinate within three weeks but some species require more time — up to a year. When seedling plants appear, raise the cover during the day for ventilation. Watch soil moisture. Don’t allow soil to dry out but also don’t saturate it. Keep temperature between 50 and 70 degrees Fahrenheit.
Transplant your plants into their permanent pots. Most cacti and succulents will be ready to transplant in 6 months to a year after germination. The right growth size for transplanting will depend on the species you are growing. Most cacti can be transplanted when they are the size of a large marble. Many other succulents may be transplanted when they are 2 to 4 inches tall. Gently lift the plants from the growing medium, set into the soil of the new container, firm the soil around the roots and water well.
Easy Succulent Propagation
If succulents are so difficult to grow from seed, how is it that we have any succulents left? In the wild, most successful succulent propagation happens not through seeds but from vegetative offsets. Many types can send out new offspring from a mother plant (think Hens & Chicks) or re-grow from a fallen leaf or a broken section of stem. The other huge advantage of vegetative propagation is that offsets are genetically identical to their parent plant. This is how we can confidently predict how our plants will look and what growing conditions they will prefer..
Watch Them Grow
Depending on the type of succulent, temperature, and sunlight, your plants may take anywhere from three days to a few weeks to begin growing. (Some may even take several months to a year to germinate, so it’s important to do your research when buying your seeds in order to anticipate growing time.) Once you see leaves begin to emerge, remove the lid during the day to keep them ventilated.
As your plants grow over the first week or two, continue to keep the soil moist and ensure adequate drainage. This is the time when their roots are just starting to develop, so it’s very important to keep them hydrated. Once the roots become established, it’s not necessary to keep the soil surface damp at all times. Monitor your plants’ growth and use your best judgment (plus your research on your particular type of succulent) until you’re watering them about once per week as you would adult plants.
This is also the time to begin to introduce your succulents to more sunlight. While succulents and cacti are desert plants, that doesn’t mean they thrive off of direct sunlight and heat. The baby plants especially do not like direct sunlight, so wait until their leaves begin to mature before slowly introducing them to more and more light. Increase the light by an hour or so every few days until you get them tolerating the amount of light in the area where you want to keep them permanently. Again, the best amount of light will vary depending on each type of plant.
Generally, it’s time to remove your young succulents or cacti from the planting tray when their size is mature enough that they won’t be damaged by handling and transplanting. Don’t rush this process, though: It’s better to keep them in a more confined area a bit longer than necessary than to uproot them before they’re ready. Usually, it’s time to replant after six months or so.
Because their root balls are fairly tight, succulents are pretty easy to transplant. Gently loosen the soil around the base and lift, without tugging on the roots, until the plant comes loose. Use your fingers to clear away the old soil and any dead roots that might be hanging off.
Make sure your new pot is larger than the old one so your plants have room to grow. Put some rocks or loose gravel in the bottom for drainage, then mix a new soil medium that’s appropriate for your succulent type. (Do not use the old soil.) Fill the new pot halfway with the new mixture, set the plant inside, and add more soil mix to cover the roots. Press the soil down gently around the base to secure it. Wait a few days before watering in order to give your plant some time to adjust to the new soil.
Ongoing Succulent Care
Caring for succulents and cacti is very easy when you know what you’re doing. Every plant type prefers different things, though, so once again it’s important to know what varieties you have to ensure the best care. In general, succulents love light, but not always direct sunlight. And with light comes heat, so consider temperature and how quickly water might evaporate when choosing a home for your plants. It’s also important to rotate your plants so that all sides get adequate light. (A leaning plant might be an indicator that it needs more sunlight.)
Overwatering is a common mistake when caring for succulents. Succulents tend to require more water in the spring and summer when the weather is warm and the plants are thriving. Make sure the soil is drying out between waterings to a depth of about one inch below the soil surface. Water the soil directly until water comes out through the container’s drainage holes. (If yours does not have drainage holes, don’t water it as much.) Most succulents require water every week or so, but keep in mind that this varies greatly depending on type and climate.
Wipe off your plants every now and then to get rid of dust, dirt, and any potential bugs. If insects become a problem for your plants, you may need to reduce the amount of water you’re giving to them. Mix a 70% isopropyl alcohol solution and spray the soil to get rid of eggs and larvae. Consider adding a small amount of fertilizer when you replant your succulents.
Our best selection of succulents
Our best selection of cactis