Hardy cacti and succulents – varieties, plants and care

The special thing about hardy cacti is the different use of water in contrast to indoor cacti. These varieties are no longer watered from September. The water that is then still in the plant body is converted into sugar by photosynthesis. In this way, the cell sap in the cactus is reduced to such an extent that the cells do not rupture even at temperatures well below 0° Celsius. The hobby gardener recognizes this fascinating process from the color change of the cacti, which takes place from green to reddish-brown in autumn. In principle, hardy cacti produce their own natural antifreeze; However, only if the hobby gardener gradually prepares them for the winter from September, as the care instructions below show.

Popular Varieties

Almost all types of cacti belong to the stem succulents, whose stems grow very pronounced. The main shoot either develops straight up towards the sky or is already branched from the base. Certain genera only develop various branches from the upper half of the main shoot. The thorns are one of the most well-known characteristics of cacti. In terms of size, the different varieties range from very small, with a diameter of just one centimetre, to very large, with a height of 15 metres. The following hardy varieties are particularly common in German gardens:

Echinocereus viridiflorus

• frost resistant to -25 ° Celsius
• profusely blooming
• up to 10 cm tall
• good for the rock garden

Echinocereus adustus G. Engelmann (1848)

• Hedgehog cactus
• needs a lot of water in summer
• rain protection is required in winter
• purple flowers up to 4 cm long

mountain cactus

• tolerates down to -20° Celsius
• should not be kept in the room
• up to 1.50 m tall columnar cactus
• Cold stimulus required for flowering
• Thorns are up to 8 cm long
• bears pink flowers in summer

Opuntia engelmannii

• hardy prickly pear to -20 ° Celsius
• grows between 1 m and 4 m high
• Fruits are edible
• grows shrubby
• intense, red plant juice

Opuntia ficus indica

• ancient prickly pear
• Fruits grow up to 10 cm
• becomes a 5 m high cactus tree
• Young plants do not yet tolerate frost
• grows particularly fast

Opuntia humifusa

• also withstands extreme frost
• presses against the ground when it’s cold
• yields large, tasty fruits
• produces yellow flowers in summer

Opuntia phaeacantha

• particularly cold and wet resistant
• grows up to 50 cm
• grows very branched
• develops attractive yellow flowers
• very suitable as a container plant

Opuntia tortispina

• hardy prickly pear
• grows very wide and 1 m high
• well suited as a pot plant
• needs the frost to grow
• develops beautiful pink flowers

Opuntia imbricata

• is one of the hardiest tree cacti
• grows up to 5 m high
• this cactus can be shortened
• Broken parts root again

Corynopuntia clavata

• hardy to -20° Celsius
• 3 cm to 7 cm tall
• yellow flowers up to 4 cm long
• needs rain protection

Kugel-Kaktus Escobaria vivipara

• survives down to -30° Celsius
• forms its own offshoots
• between 10 cm and 15 cm tall
• needs cold stimulus to bloom

More succulents

Although most home gardeners think of cacti when they think of succulents, there are many other succulents. Some of these are hardy, like the agaves, which look very similar to the cacti. Below are some of the most popular strains:

New Mexican Agave

• tolerates temperatures down to -20° Celsius without any problems
• forms bluish rosettes of leaves
• does not tolerate rain
• grows up to 1 m in diameter
• thrives better as a container plant

Agave megalacantha

• Extremely robust against cold and wet
• a rarity among the agaves
• Propagation only via offshoots

Agave parryi

• hardy to -20° Celsius
• requires a rain-protected location
• reaches up to 80 cm in diameter
• makes spectacular flowers up to 5 m high

Agave utahensis

• It doesn’t mind frost down to -20°
• requires direct sunlight
• only plant out when they are 2 years old
• develops impressive flowers

Agave Queen Victoria

• the queen of the agaves
• compact and regular rosettes
• tolerates even the strongest frost
• forms sensational flowers

Hardy cacti and succulents may be classified differently from a botanical point of view, but they have broadly similar requirements in terms of planting and care.

plant

From the point of view of climatic conditions, you can cultivate hardy cacti and succulents in all regions of Germany. They tolerate at least down to -20° Celsius and can therefore be planted out in the garden without any problems. With some varieties, however, the young plants are not yet frost-resistant. They are therefore raised indoors or in the greenhouse for the first 2 to 3 years and only then move to the outdoor area. Many of the most popular cacti and agaves make a beautiful picture as a container plant and decorate the house entrance, the terrace and the balcony even in the cold season. In order for the planting to be successful, the following instructions and tips should be observed:

• best planting time March to August;
• do not water immediately after planting;
• a weed fleece is ideal;
• sunny and rain-protected location;
• southern hillside is perfect;
• water-permeable soil;
• rainwater drains well;
• nutrient-poor, granular substrate;
• Compost promotes fungal diseases;
• substrate layer at least 20 cm thick;
• Waterlogging is deadly.

However, some particularly robust cacti, such as the Opuntia phaeacantha, can do without a rain-protected location. So that the soil or the plant substrate is really airy and granular, it makes sense to mix some quartz sand, rock granules or gravel under the potting soil. However, conventional potting soil is not suitable because it is enriched with too much nitrogen fertilizer. The commercially available cactus soil is more suitable as potting soil. In tubs or other planters, care must be taken to ensure that there is a sufficiently large drainage hole for the irrigation or rainwater, covered with broken potsherds, gravel or weed fleece as drainage. If you bring the hardy cacti and succulents into the house in winter out of misunderstood pity, you will do a lot of damage to them.

Advice and advice on care

When the cacti and succulents go into hibernation with the first frost, they are no longer watered. In March, they are then awakened from hibernation with the help of small amounts of water. Even if the plants look shriveled, you should only gradually increase the amount of water during the month. The following care instructions then apply from April:

• water regularly;
• at least once a week;
• get rid of weeds immediately;
• Let plant wounds dry;
• supply with complete fertilizer every 3 weeks;
• do not fertilize from August;
• do not water from September;
• do not remove snow in winter;

When the cacti start to turn reddish-brown in the fall, that’s the sign they’re building up their winter shelter, as detailed above. Depending on the variety, it is now important that they are protected from the rain.

Rarely repot

Anyone who cultivates their hardy cacti and succulents as a container plant should repot them about every 2 to 3 years, at the latest when the pot is completely rooted. The best time for this is after the end of the dormancy period between March and May. Since this process can be quite painful due to the thorns, clever hobby gardeners wrap the plant with foam rubber. By the way, columnar cacti can be moved very well with the help of padded test tube tongs. The root ball comes out of the old pot most easily when it is dry.

After repotting, the plant is cleaned of dead and rotted roots and then inspected for pests. Roots that are too long may be shortened a little. The new planter is prepared by laying a thick layer of drainage, e.g. B. is formed from basalt chippings, potsherds or gravel. Then some plant substrate consisting of cactus soil, quartz sand and granules is filled in before the cactus or succulent is completely potted. The first watering is only 1 to 2 weeks after repotting, because first new roots have to form in the fresh substrate.

Propagation by seeds and cuttings

Seeds of the most popular cacti and succulents are available in specialist shops. In view of the large variety of varieties, it is worth considering carefully which of the hardy plants you sow, because this process requires a lot of patience. Good seed soil is also commercially available. All containers that are covered with foil, glass or a transparent lid and that also have a drainage hole for the irrigation water are suitable as sowing containers. After the seed compost is in the jar, gently push the seeds in, but don’t cover them with the soil, as they need light to germinate. The first seedlings usually appear after about 10 days. It then takes another 3 to 4 weeks until these are pricked out and repotted. Important is,

Depending on the variety, the young plants are hardy from the start or are first grown indoors for 2 to 3 years before they are planted in the bed. However, vegetative propagation using cuttings and side shoots is somewhat less complicated and faster. Many cacti and succulent varieties already form their own offshoots, called Kindel. These are simply separated from the mother plant with a twisting movement, placed in the substrate and they form their own roots. If it is necessary to cut cuttings, this should be done during the growth phase with a sharp and disinfected knife. Then the interface must dry thoroughly before the cutting can be inserted into the soil to form roots there.

Conclusion
In particular, hardy cacti and succulents beautify the gardens all year round. Basically, they are not very demanding in terms of plants and care. Nevertheless, it is important that you follow a few important tips so that the cacti and succulents grow and thrive for many years and beautify the garden with their beautiful flowers.