Most cactus are usually dormant during winter and active during summer. However, some are active during winter. Christmas cactus and Thanksgiving cactus bloom in winter. We know how unfriendly winter can be, and your cactus needs to be taken care of with caution. I sought to find answers on how you can care for your cactus in winter, and I made some pretty exciting discoveries.
Bringing Your Cactus Indoors in Winter
If your cactus has been outdoors during spring and summer, you need to bring it indoors in cooler weathers. This way, your plant will gradually transition without having a ‘shock.’
- Move your cactus to a shade outdoors, which receives about one or two fewer hours of direct sunlight daily for 1-2 weeks. Do this just before winter when the temperatures are expected to be below 65F at night.
- Move the plant again to a place that receives one of two fewer hours of sunlight as compared to the previous place.
- The idea of moving the cactus gradually is so that it gets used to the temperatures for it to avoid the ‘shock.’ Take the cactus indoors and find a sunny spot. A south-facing window would be perfect. Try keeping the cactus warmer in temperatures of 65-90F. All this is in preparation of winter dormancy.
- Make sure you don’t fertilize the plant during winter because it is dormant.
To encourage your cactus to go dormant, you need to reduce your feeding schedule to make it less. Don’t water frequently but rather do it possibly once a month.
Caring for your Cactus Indoors in Winter
1. Place your cactus strategically
As mentioned, it is advisable to bring your cactus indoors to avoid the harsh winter conditions. Some people opt for different types of grow lights to provide ample light for the plant. However, unless your home is extremely dark, it may not be necessary to purchase these lights.
Place your plants strategically at a place where they will receive the most light as possible. The light should be sufficient enough to keep your cactus colorful for the few cold months. If you have more than one cactus plant, keep rotating them so that they all get enough light.
If you are in the northern areas that experience some harsh winters, don’t place your cacti too close to the window. The cold coming in maybe too harsh to them and they may end up not doing very well.
2. Grouping your plants
If you are a massive cactus lover, you may probably have a collection of different species. As mentioned earlier, some species are active during winter. The idea is, initially, if you started growing the cacti from seed, you should have probably labelled them. Even when you propagate using cuttings, labelling is essential as this helps you know the particular needs for the plant.
Know each of the plant’s water and light requirements. Cactus are quite sensitive to overwatering, and you need to water just the right amount. You don’t want your roots rotting slowly and the cactus eventually dying.
Group them in sections of those active and dormant during winter and their different light requirements. That helps reduce the possibility of making mistakes during their feeding time. If you are not quite sure about the schedules, there’s a lot of research online that has been done on different species. This would be resourceful.
3. No feeding and less watering
As cacti are more prone to rotting as compared to other succulents, proper care needs to be taken to avoid such incidences. Some common signs of root rot are black or colored dots on cacti skin, discolored scabs, sunken spots, and you may even see some oozing of the cactus.
You need to take into consideration what happens below the soil which you can’t easily see. Cacti depend on the root hairs to provide nutrients. If they start rotting, that means nutrients are not readily available, which drives the cactus to the above signs of root rot. These plants can take some underwatering for some time, but overwatering is pretty bad for them.
Keep in mind that you should keep the roots happy when watering. This means just enough water to prevent them from drying. Since most species won’t flower in winter, that means the growth rate will be pretty low. Therefore, they just need enough water for survival.
Also, avoid feeding them. Don’t use any fertilizer at this point as they may end up becoming weak. Keep the water levels low and only water when they really need it. You can use a wooden stick to poke the soil until the lowest point before watering to see if the soil is still wet. Only water when the stick has no soil remains to stick on it.
The issue of watering is quite sensitive. If you adhere to the above, you might find that your plant only needs water once a month or even longer. Be careful not to underwater such that the soil starts to pull away from the sides of the container. The roots may end up desiccating and collapsing.
The pot you use is a huge determinant of the plant rots. Get a suitable container, preferably terracotta pots that have drainage holes. The importance of these holes is to ensure that any excess water is drained away to avoid water sitting in the soil for long.
You probably are aware that even the soil you use is a major determining factor how your plant thrives. There are readily available cactus soil mixtures which you can purchase in local garden stores. You can also order online, and they can be delivered to you. Make sure the mix you go with has some coarse sand and vermiculite. The soil mixture and the pot work hand in hand to ensure your cactus doesn’t die of root rot.
4. Choose your cactus wisely
Purchasing cactus should not be complicated. However, make sure you choose the best species, one that works for your environment. Some cacti species are more tolerant to the freezing temperatures of winter compared to others.
Consider choosing a cactus that will survive through winter. At times, you may need to cover your plants to retain air and moisture to prevent ice from destroying the stems and trunks.
Some types of cold-hardy cactus
- The Claret cup cactus
This particular species is from the Echinocereus group. They can withstand temperatures of -20 degrees Fahrenheit/28 degrees celsius. If they are indoors, they can even withstand lower than that.
- Mammillaria Bocasana
This type of cactus belongs to the Mammillaria group that are usually ball-like. Once they mature, they can form rolling mounds of tiny bits of cactus. They can withstand temperatures as low as -20F.
Opuntia is also another group of cacti that’s cold-hardy. Prickly Pear is the most common type in this family. Not only is it among the fast-growing cacti, but it is also drought-tolerant, which means it doesn’t need frequent watering. They grow to an approximate height of 12 inches.
One of the popular types of this family is the Mountain spiny star. They are ball-like, and they have a high resistance to cold. They also have the potential of growing up to 12 inches high.
Lee’s dwarf snowball, plain’s pincushion, and beehive cactus are some of the popular types in this category. They are very tiny but produce big flowers.
5. Insect management
Homes will tend to be dry during winter. This is because there are all kinds of heating systems to keep the house warm from the heaters to the furnaces. Insects such as mealybugs love warm places and are most likely to attack your cactus.
It is natural for you cactus to be insect-infested. What you do to manage them is what matters.
They are usually ⅓ or ⅕ inch long and resemble cotton as they appear waxy. Mealybugs are usually in a cluster and move slowly. They are mostly found on cactus leaves and other hidden parts of the plant.
We also have root mealybugs that suck the root juices and live in the soil. When they suck these juices, root rot is almost nearly inevitable, and they end up causing bacterial infections.
They are usually ⅛ or 1/16 inch and look like black flies that can easily be confused with mosquitoes. Mostly, they hover around the soil surface. What’s interesting is that the adult flies can’t harm the cactus, but the larva is pretty dangerous. The larva lives in the soil and consumes both the roots and organic matter, which are meant to provide nutrients to the plant.
Fungus gnats are more likely to affect cactus seedlings as compared to fully grown cacti, and they may end up killing the young seedlings.
The first sign that spider mites infest a cactus is the webbing. You will also notice brown spots on younger plants on the epidermis. In terms of size, they are about 1/50 inch. If you try tapping the affected area, they look like dust. They suck the plant’s juices.
Scale insects, just like mealybugs, are cotton-like and they attache themselves to leaves and stems but can be scraped off.
Try and control these insects so that they don’t destroy your cactus. Get a safe remedy. First, to avoid the attacks, you need to grow your cactus in the right conditions. Make sure if it’s winter you ensure they are getting just the right amount of heat and light.
For spider mites and mealybugs, you can wash them off. Cover the soil you’ve planted your cactus in to avoid it being washed away and pour a lumpsum amount of water on the plant. The insects should be washed away.
Consider spraying the plant with a dilute alcohol solution of 1:3 with the ratio being alcohol to water.
Prevention is better than managing the insects when they have already attacked your cactus. Hygiene should be a priority when growing these plants. Always be on the lookout for dead leaves and discard them as they are a hot breeding ground for pests. Keep your plant in the recommended conditions such as the right sunlight and watering them only when they require the water.
Caring for Christmas Cactus in Winter
Like previously mentioned, unlike most cacti species that are dormant in winter, the Christmas cactus is active at this particular season.
The Christmas cactus prefers bright but indirect sunlight. If you decide to grow them indoors, protect them from the southern and western sun exposure. They do well in warm temperatures of 70-80F.
During winter, try to keep your Christmas cactus in the evening at temperatures of 60-65 °C. It is more likely to form buds in temperatures between 50-55 °C.
A word of caution is to avoid putting them in cold drafts and also keep them away from home heaters or fireplaces. Remember to fertilize them in spring when growth appears.
Christmas cacti love humid environments. For people who live in arid areas, it’s essential to keep your plant moist. The easiest and best way to do this is just placing a tray of water near the plant. The water will evaporate into the atmosphere and provide the needed humidity.
Another alternative of providing humidity is getting gravel and putting it in a dish then filling it with water. Then place your potted cactus in it. You can also mist your plant with a spray bottle.
The cold-hardy Christmas cactus
The Christmas cacti tend to bloom around Christmas hence the name. They flower during winter to produce white, red, pink or lilac flowers which are usually 3 inches long. The cold hardiness of this species is higher than for other cacti. They can’t withstand frost, but they need cold temperatures to force bloom.
How to treat a Christmas cactus exposed to cold
As much as these species bloom in winter, they also don’t love freezing temperatures. If they stay out too long, the water that’s usually stored in the tissues will freeze making them expand. This damages the stems.
Once the water thaws, the tissues will contract, but they will be left damaged. This, in turn, leads to rotting spots and dropped leaves.
When you notice your cactus looks like this, you need to treat it and try to revive it. The first step is removing any tissues that seem rotten. Water the plant lightly and place it at temperatures of 60F or 15 °C. Monitor the plant and if it survives at least six months, you can then fertilize it using a cactus-specific fertilizer. It only requires diluted solutions.
The idea is, if you grow your Christmas cactus outdoors, you need to take it indoors when the temperatures are extreme to avoid doing damage control.
To encourage the blooming and healthy growth of your plant, make sure you consider repotting. You can re-pot any time between 1 and 3 years. Sometimes, you’ll notice that your cacti roots are poking their way out of the drainage holes. This is a clear indication you need to re-pot.
All in all, proper care should be taken to all cacti species because they are more likely to have damages in these extreme weather conditions. The above tips should help your cactus stay safe.
How can I cold protect my cactus? Cactus need to be protected from the freezing winter temperatures. If your cactus is in container plants, you can quickly bring them inside your house to protect it from the freezing temperatures outside. Alternatively, for the landscaping plants, you cover them with frost blankets or bedsheets during late afternoons. Make sure the covers don’t touch the plants. You can look for support frameworks. You can remove the coverings the next day when the temperatures rise above freezing point.
Can cactus survive with artificial light indoors? When you decide to grow your cactus indoors, you need to consider the light aspect. Light may be insufficient, and they may not thrive. Artificial lights act as a substitute for sunlight. They grow well with no issues. Make sure you attach your grow lights to a timer so that it’s easier to control the light the cactus receives.
Why does a cactus turn yellow? There are a few reasons why cactus turn yellow. One, they can be sunburned. If they have been living indoors and are taken under direct sunlight, they will certainly become yellow. Introduce them to direct sunlight gradually to avoid this. The other reason is that they may be infested by pests such as mites. These little animals such the cacti tissues. Lastly, it could be because of root rot. Rotting is one of the significant effects of overwatering your cactus. Avoid overwatering; you’d preferably underwater than overwater.