How to Grow Cacti in a Greenhouse? A Complete Guide to Practical Tips
Plant lovers who want to grow cacti in a newly built greenhouse sometimes face this question: when cultivating cacti in individual pots on greenhouse benches or transplanting them into a planting bed, which of the two methods is better? Opinions vary widely on this point.
Pictured: greenhouse cactus cultivation
When transplanting cacti into a greenhouse planting bed, people can use decorative stones (such as large lava fragments) to create a cactus landscape. In this way, large spherical cacti, columnar cacti or cactus clusters can freely spread their root systems, which are often several meters long. They present a growth stance of vigor and health never seen before, and species that only flower when they grow very large also produce beautiful flowers. The amount of watering is also less than usual, because the root systems of large cacti extend downward to a great extent, and fully watering 3-4 times during the growing season is already enough.
Preventing external cold from penetrating into the base layer of the soil is an important prerequisite for the rapid growth of cacti in a greenhouse planting bed. Laying a thick layer of polystyrene foam board deep in the foundation can also provide effective heat protection. This should be considered when building the greenhouse, or at least before planting the cacti. Warmth-loving cacti such as the decorative golden barrel cactus with colored hooked spines, and large sea-urchin cactus balls. Many columnar cacti or plants of the genus Selenicereus all want a warm environment underfoot. If external cold penetrates into the planting bed, the transplanted cacti will grow poorly. In addition, the soil in the greenhouse planting bed must have very good air permeability, especially the surface layer of the soil. After watering, it should dry quickly, and waterlogging must not occur; water should be able to seep in quickly.
A relatively large cactus planting bed gives pests (such as root lice or nematodes) the possibility of "unlimited" spread. Therefore, measures should be taken before planting to prevent the invasion of pests. The soil in the greenhouse planting bed should not contain pests, and all transplanted cacti must be carefully checked for pests before being planted into the bed. Of course, pest and disease problems also exist in individual pots, but such pots can be isolated and treated relatively easily.
When planting, attention should be paid to the different growth habits and future external size of the transplanted cacti. Care should be taken not to plant them too densely, otherwise every later repair and operation to create more space for the plants in a densely growing cactus bed or to remove dead plants is very difficult.
Cultivating cacti in individual pots makes the following procedures easier, namely regrouping the plants, giving a fast-growing plant a larger pot and thereby providing it with more soil foundation, curing pest and disease problems, or photographing the flowering situation. People can water each pot individually, but generally speaking the watering frequency is more frequent. Pots placed side by side cannot form a beautiful cactus landscape, and if done this way, large spherical or columnar cacti will grow weakly, and their flowering will also be reduced compared with usual.
Small and slow-growing cacti should not be transplanted into the planting bed together with large cacti. Small cacti cannot withstand the competition from the root systems of large cacti, because the roots of the former cannot extend into the deep soil. Crowded out by imposing columnar cacti and tall spherical cacti, small rare varieties in the cactus planting bed will develop poorly, and their growth will be worrying. Many cactus lovers try to solve this problem with a compromise: if the size of the greenhouse allows, they place the small spherical cacti grown in pots on benches at the edge of the greenhouse, and then transplant the large cacti into the planting bed in the center of the greenhouse.
Of course, people can also create a "landscape picture" when cultivating cacti in individual pots. In order to obtain a more uniform moisture balance, people can plant cacti grown in clay pots into a peat and sand-gravel mixed soil, as already mentioned in the previous chapters. Some plant lovers also place plastic flower pots or larger individual pots in gravel, crushed lava, or even furnace slag. People can combine these pots freely and place decorative stones in the gaps. However, when an individual pot is taken out for photographing, the foundation around it often loosens and shifts, and putting this pot back in place becomes difficult.
Recommended articles:
A Brief Introduction to Cactus Cultivation in Plastic Pots
Cactus Cultivation Techniques in Clay Pots
A Brief Preface to Cactus Cultivation
The Main Places of Origin of Cacti, and an Introduction to Their Origins
The Places of Origin of Cacti, and Their Distribution Factors