General information about the cacti
Locations of cacti
For good growth Cacti not only need certain growth factors but also the type and choice of location depends on whether the factors can contribute favourably to the plants or not.
Sunlight is extremely important especially for cacti. In their habitats they have at least twice as much radiation available which explains their choice of location.
No matter where we want to cultivate cacti, on the window sill, the balcony, in a cold frame or in a greenhouse one thing should all these places have in common, namely direct sunlight and fresh air. However it must be ensured that the plants can have a resting phase in the low-light winter months at a place with cool temperatures.
3. Cold frame
Most frequently cacti are cultivated on the windowsill. But this is the place where most of the collections began. If you began to like these plants and also got success with flowers new plants come quickly to the collection. If you then also get infected by the incurable virus for the passion of collecting cacti you can quickly run out of space.
What conditions have our plants on the windowsill?
First the climate the room is vital. Furthermore the direction of the window is also vital. A south side window is always first choice. If you can’t provide that an east side window is more preferred than a west side window.
In an east side window the light intensity and warmth of the morning rise slowly. In a west side window the plants receive sunlight only when it is already strongest. The effect would be burnings on the plants. North side windows are unsuitable for the cultivation of cacti because they get not enough sunlight.
Under this condition you can only cultivate Epiphyllum, Rhipsalis, Selenicereus and Schlumbergera with success.
You should also note that shady trees or buildings can obstruct direct sunlight.
Most important is that there is always the possibility to ventilate and the possibility of shading if the sunlight is too strong. Another important aspect is the observance of the rest during winter with temperatures in the range of 5 to 15°C (41 to 59°F). Who wants to have such temperatures during the heating season in the living room? Make sure during the winter that the windows close tightly and avoid cold or frosty drafts. A radiator which is installed under the window may disrupt the winter rest of our plants.
Owners of a sunny balcony can offer their cacti a good location. Here the plants receive constantly fresh air and direct sunlight. A possibly existing roof overhang protects against too much rain. If this isn’t possible a good drainage in the pots is important so that too much rain water can drain fast. If you want you can also build a small roof of corrugated polyester or something else to protect the plants. It keeps the rain away from the plants and can be very easy removed during sunny weather.
Here the collector has much more space to build a much larger collection. The space can be enlarged by established of shelves. However, it must be ensured that a light and frost-free space is available for the winter rest. The cacti have to be brought there before frost in fall.
In this care you get healthy and well-hardy plants with beautiful and strong spines.
3. Cold frame
If you own a garden you have the possibility to cultivate your cacti year-round in a cold frame. The orientation of simple cold frames should always be that the rear wall shows to north and the front wall shows to south. With double cold frames the side walls are showing to north resp. to south so you can get the greatest possible radiation.
Before establishing a cold frame you should prepare the stand a little. An insulation in the soil with styrofoam can be made. This protects against frosts and reduces a rapid cooling of the cold frame. A good drainage with coarse gravel or crushed stones is also very important and essential. The size of the cold frame depends on the quantity and size of the cacti which will be cultivated therein. There are countless models available which makes it easy to find something suitable for everyone.
For the cultivation in a cold frame it must be emphasized that the plants get a higher amount of heat. The small air space heats up very quickly and retains the heat. But this may also cause a congestion of heat due to insufficient ventilation which leads to damages on our plants. So you always have to mind for good ventilation, so that the cold frame does not overheat. Some manufacturers offer automatic window-opener for their cold frames. They open or close the window automatically when a previously set temperature is reached. If a long fair-weather period is forecasted the windows can be completely removed. This has the advantage that the plants get the unfiltered sunlight. Even an occasional light rain does no damage and if the bad weather continues just put on the windows again.
Especially in late summer the windows should also be opened overnight. Because much fresh air and slightly lower night temperatures harden our plants and make them more resistant against diseases and pests.
At the beginning of the cold season it is necessary to install an additional insulation. This can be done with styrofoam. The remaining windows are insulated with bubble wrap.
An electric heater keeps the cold frame frost-free and provides adequate air movement. But even in winter it is important to ventilate the cold frame on frost-free days to reduce the high humidity.
What collector doesn’t dream of its own spacious greenhouse in which he/she can concentrate on its hobby independent from weather and season? Only the available space and the financial resources determine the size and shape of the greenhouse.
You not only have to mind the acquisition but also the accruing energy costs if the greenhouse will be heated in winter.
Which type of culture you chose is up to you whether in greenhouse pots and bowls on tables or free planted in a flower bed. Both culture methods have advantages and disadvantages. On the one hand plants in pots and bowls can be removed from the collection to take pictures or just to look at their roots on the other hand planted cacti can propagate freely and show thus a very large and rapid growth. But who would like to cut a beautifully grown Opuntia or a columnar cactus with a saw or a knife?
The cultivation in a greenhouse is much easier. Also the conditions for the plants are perfectly. The existing airspace is warmed in the sunshine only very slowly and also cools very slowly again. If it’s too hot the automatic window openers do the ventilation. One shade which is located under the roof can be operated by a motor and can also be closed or opened.
At the beginning of the cold season the greenhouse is also insulated with styrofoam and bubble wrap. This helps to reduce energy costs for many times over. An electric fan heater with thermostat does the heating. Only in case of power failure you have to have at last a resort at hand. This may be a small gas heater. But as this produces exhaust gases and water vapour it is not recommendable for a long time use.