Growing Cacti from Seeds
Growing plants from seeds is not as hard as you might think, even though many of us have tried and failed! One of the most common mistakes people make is planting the seeds too deeply. It would be best if you only planted seeds deep in the soil as the seed is wide. When seeds are planted too deeply, the tiny plants emerge and begin to grow but do not reach the surface before they run out of stored food. Follow these instructions for growing cacti from seeds, and you will surely be successful.
It is best to use fresh seeds when growing most cacti. Seeds can be obtained from a commercial source or collected from a plant in your collection. Take care when collecting seeds from a cactus collection. Some cactus species hybridize freely, and true seed cannot be assured unless pollination has been monitored carefully.
A good potting mix, amended with ½ its volume of granite, perlite, or pumice for drainage, makes a good mix for growing cacti from seed. The soil must be as pest-free as possible. To pasteurize soil, put it in a shallow heatproof pan, place it in the oven at 300 °F (150 °C) for 30 minutes. Most commercial soils are at least pasteurized, if not sterilized. Check the label.
Be sure that all containers to be used are clean. The type of container is not important, but shallow ones are preferred. Water the soil thoroughly and let it drain completely before planting. Spread the seeds evenly over the top of the soil. Cover the seeds lightly with the mix or very fine sand. When planted, cover the container with any transparent lid. This will retain moisture and allow light to reach the seedlings.
Cactus seeds need both light and warmth to germinate. A sunny window is a good location, but be careful the light is not too strong and therefore too hot. The moisture retained by the cover should be sufficient to germinate the seeds. Most cactus seeds germinate within 3 weeks, but some take much longer, be patient. Once the spines are showing, raise the cover for ventilation during the day. Do not allow the soil to dry out. The amount of water will depend on how much light and heat the seedlings receive. Watch the seedlings carefully. Do not swamp them in puddled water but do not let them dry out completely.
Seedlings are ready to transplant into larger containers when they are the size of marbles, between 6 months to a year after germination. Be sure the soil mix is very well-drained, and the container is no larger than twice the plant’s diameter. Plants can be grown in clumps or groups of 6 to 8 per pot at this size until they are about 1 inch (2.5 cm) across, then separated and individually reported. Lift the small plants carefully from the growing mix, place in the new container, firm the soil around the roots, and water in.
It is usually best to let the young plants recover from transplanting in a shaded area. Even in cacti that naturally grow with full sun, seedlings will be tender to the full sun until they are older. Acclimate a young plant to the sun gradually, beginning when it is about 1 inch (2.5 cm) across. It is often easier to acclimate young plants to the sun in the winter and provide some shade in the summer until they are about 3 inches (7.5 cm) across.
Fertilize young seedlings monthly in the growing season, usually the warm season. Use a formulation specifically for cactus or an all-purpose soluble houseplant formula at ½ the recommended strength.
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Follow these instructions for growing cacti from seeds, and you will surely be successful. It is best to use fresh seeds when growing…
How To Plant Cactus Seeds – Tips For Growing Cacti From Seed
With the increasing popularity of succulent plants and cacti, some are wondering about growing cacti from seed. Anything that produces seeds can be reproduced from them, but this is not true of every seed. Cactus seed growing might move along easily without your help if conditions are right, but this is unlikely. Some seeds that drop in the natural habitat may take many years to germinate. Getting them started may be a process you’ll need to do yourself. Successful cactus seed germination results in more plants to expand your collection.
How and When to Plant Cactus Seeds
Seeds form in blooms of the cactus. If you wish to attempt collecting them, remove flowers as they fade and place in a small paper bag. You’ll find the seeds when the flowers have totally dried up. You may also purchase seeds, as many are available online. Check to make sure you’re purchasing from a reputable source. You want healthy, viable seeds to sprout.
Dormancy of the seed must be removed before it will sprout. Several means of removing the dormancy factor are important when learning how to plant cactus seeds successfully.
Nick the tough coat covering the seed. Soaking seeds before growing is necessary for some types. Opuntia, for example, is one of those with a tough seed coat and will germinate more quickly if the seed surface is abraded and soaked. Opuntia seeds also benefit from the cold stratification process. For the most successful seed growth, follow the steps in this order:
- Scarify the seed, making a small opening, with sandpaper, a small knife, or your fingernail.
- Soak in lukewarm water for a few days, changing the water daily.
- Stratify by placing in soil in the freezer or outdoor cold for 4 to 6 weeks.
After the completion of these steps, plant your seeds into a moist, well-draining seed starting mix and cover. Do not plant deeply. Some, such as golden barrel cactus, can be just laid on top of the soil. No more than a light soil covering is needed for others.
Locate in a bright area, but not direct sunlight. Filtered sunlight is acceptable. Even though cactus grows in dry areas, it requires high humidity to germinate. Soil must remain moist, but not soggy. Seeds will sprout in a few weeks to a few months. Patience is a virtue.
Above soil growth develops before the root system, according to cactus seed growing info, so consistent moisture and high humidity is necessary until roots are well-developed. This is normally until the plant fills the small starting container. You may then transplant your seed-started cactus.
With the increasing popularity of succulent plants and cacti, some are wondering about growing cacti from seed. Successful cactus seed germination results in more plants to expand your collection. Learn about cactus seed germination in this article.