How to Grow Your Own Cactus From Seed

When you think of plants typically grown from seed, cacti are probably not the first things to come to mind. In fact, you may not have even considered it an option. But it certainly is, and it’s incredibly rewarding.

If you love cacti and want a garden full of them, buying established plants can be quite pricey. When growing from seed, you can grow far more plants from a small packet than you could buy at the same price. It also gives you a rare opportunity to watch the whole lifecycle of a cactus, from tiny sprout to flowering succulent.

Growing cactus from seed is not difficult. Even complete beginners won’t struggle with the process. But it does require patience—your young plants will only reach about an inch tall after a year of growth. Luckily, the reward you get is well worth the wait.

All Kinds and Forms Mixed Cacti Seeds

Form a deeper relationship with cacti by nursing them from seed. Naturally slow to germinate, but once established, this interesting mix of desert plants will practically grow themselves!

Buy at Botanical Interests Shop

What You’ll Need

The first thing you’ll need is, of course, cactus seeds. You can find a specific variety or a mixture containing a few different species. The Botanical Interests All Kinds and Forms Mixed packet contains six different types, including:

• Saguaro cactus
• Emory’s barrel cactus
• Southwestern barrel cactus
• Arizona barrel cactus
• Prickly pear cactus
• Strawberry cactus

Next, grab a container. You can use any container for sowing, as long as it has plenty of drainage holes. Because the young plants remain small for a while, you can also use seedling trays, but sowing directly into a container saves you the effort of transplanting later on.

To fill the container, you’ll need a cactus soil mix. To ensure germination, this mix should be relatively fine and not chunky, draining quickly to prevent rot. Either purchase a succulent and cactus mix or make your own by combining:

• 2 parts potting mix
• 1 part perlite
• 1 part coarse sand

Vermiculite is a great addition to sprinkle over the top after sowing. But you can also use more of your potting mix if you don’t already have vermiculite on hand. A germination dome is also helpful to maintain humidity and boost germination. If your container is too large, a clear plastic sandwich bag produces the same results.

When to Sow

One of the best parts of growing cactus from seed is that you don’t have to wait for a particular time of year to start. Since you can sow indoors and keep them inside for at least a year, there is no concern about climate or outdoor extremes damaging young plants.

If you’re looking for something to keep you busy in the middle of winter when other gardening activity slows down, why not grow cactus from seed?

How to Sow Cactus

Once you’ve gathered all your materials, follow these easy steps to sow your cacti. For those who grow plants from seed regularly, the process is the same as for any other plant.

Soak

The first step is optional but can help improve germination rates. Soaking your seeds for a couple of hours (or overnight) before sowing softens the outside of the shell, allowing moisture to penetrate and making it easier for those young fragile roots to reach into the soil.

As your soil mix will be moist after sowing, this step is not absolutely necessary. The seeds will still germinate without this extra help. But for tough species, like the prickly pear, this quick soak gives them a little extra boost to speed up the germination process.

Only soak the seeds right before you’re ready to plant. After soaking, they need to be sown immediately. Simply submerge them in a glass of lukewarm water to soak them for a few hours.

Prepare the Container

While your seeds are soaking, prepare your chosen container. Fill it with your cactus mix (if you’ve made your own, make sure it’s mixed well before filling). Press it down lightly to remove any large air pockets, but don’t compact the soil too much.

Just before you’re ready to sow, moisten the soil with a watering can or spray bottle. The soil should be moist before sowing so you don’t dislodge the seeds with a stream of water after planting. This also gives you a chance to check the soil is draining well before sowing.

Sow

Grab your packet of seeds and sprinkle them lightly over the top of the soil. They can be spaced close together as the seedlings will stay small. The general spacing recommendation is 1/8″ to 1/4″.

After sowing, press them very gently into the soil surface. This will ensure they are in direct contact with the soil (and soil moisture), facilitating germination. They don’t need to be planted deeply—in fact, planting too deep will hinder germination.

Cover

After sowing, cover the top of the seeds lightly with a layer of vermiculite to help with moisture retention. If you don’t have vermiculite, a layer of additional cactus mix will work well, too. You want them to be surrounded by moisture to boost germination.

Humidity and heat are also important factors to consider in the germination process. To trap humidity and warmth, cover the container with a germination dome or plastic bag. If the bag is collapsing, use skewers to hold them in place above the container.

Place the container in a warm area in bright but indirect sunlight. Avoid direct sun while the plants are still young.

Care

Now comes the hard part—patience. Some cactus varieties can germinate in less than a week, while others can take up to three months to emerge. Don’t be discouraged if you don’t see any activity within the first few weeks. These adorable cacti will keep emerging over time as long as conditions are consistent.

Although cacti are sensitive to moisture, the seeds do require consistent moisture to germinate. In the first few weeks, keep the soil lightly moist but not soggy to encourage germination and root growth. Also keep the container covered, removing the dome to water and allow airflow.

Once green growth appears throughout the container, you can remove the cover and slowly increase light exposure, avoiding harsh direct sun. Continue to keep the soil lightly moist—it takes a while for these slow-growing plants to develop their root systems.

Transplanting

As I mentioned, your young cacti will only be about an inch tall after an entire year of growth. They can stay in their original containers for several months without trouble. Once they start looking a little crowded, it’s time to transplant.

Transplanting cacti is a little tricky thanks to the large spikes that usually get in the way. When you’re ready to transplant, make sure you’re wearing gloves and grab a small fork or set of tweezers.

Gently lift each individual plant with a fork and replant into small containers with fresh cactus mix. You can use the same mix as you did previously. After transplanting, limit your watering and allow the soil to dry out completely between watering sessions.

If you want to transplant outdoors, give your plants time to adjust to outdoor conditions. Move the containers outdoors for a few hours each day, slowly increasing the time over about two weeks. Don’t thrust them into harsh weather and full sun as the cacti will struggle to establish.

If you want a continuous supply, sow new cactus seeds each year to continue filling your garden. Or, you can wait a few years for your cacti to mature before collecting seeds from them and starting the process all over again.