Prickly pear and other cacti go dormant in winter, and their pads appear to dry up or deflate. They will return to their normal plumpness in spring when you can prune off any unsightly pads or deformed growth.
Light
As a desert cactus, prickly pear thrives in full sun. That means at least six hours of direct sunlight per day. Indoors, a west- or south-facing window works best. In very hot climates, some shade during midday can prevent scald.
Soil
The most important requirement for any plant in the Opuntia genus is soil that drains well. Prickly pear easily grows in sandy or gravelly soil, but it can tolerate other soil types as long as there’s good drainage and not too much water.
Water
Prickly pear likes dry conditions, and very little watering is required to maintain the plant. This is why the cactus is often used in low-water gardens. Limit your watering to every two to three weeks or whenever the soil is completely dry. When watering, simply moisten the soil without soaking it. If you get minimal rainfall, that’s often all the plant needs. When growing prickly pear as a landscape plant in regions that get lots of rainfall, it’s critical that the soil be extremely porous and well-draining.
Temperature and Humidity
Prickly pear cactus thrives in hot, dry desert summers. But many of its species have good cold tolerance. (Remember, desert nights can be cool.) It generally does well in regions that have mild winters and hot summers with low humidity. Prickly pear can struggle in areas that have very high humidity, even if the temperature is to the plant’s liking. Typical indoor temperatures and humidity levels are usually fine for a prickly pear grown as a houseplant. However, keep the plant away from heat and air-conditioning sources, as they can cause extreme temperature fluctuations.
Fertilizer
Prickly pear rarely needs fertilizer when planted in the ground, unless you have very poor soil. In containers, it will use up the soil’s nutrients faster and will require some feeding. If the plant’s green pads start to appear dull or if the plant doesn’t flower, that can mean it needs food. You can apply a balanced fertilizer during the growing season, following product instructions. You also can choose a high-nitrogen fertilizer for larger pads or a low-nitrogen fertilizer for more flowers and fruits.
Types of of Prickly Pear
Of the many species of native prickly pear, a surprisingly large number have uses as garden plants and houseplants. Local garden centers will normally offer only those that are suitable for your climate. Here are some favorites:
Opunta humifusa (formerly O. comressa): Known as eastern prickly pear, this species is a sprawling, ground-hugging cactus that grows up to 12 inches tall and wide. It produces yellow flowers with orange splotches from May through July. It is hardy in zones 4 to 9. This is one of the most popular prickly pear species for garden cultivation. ‘Opuntia microdasys ‘Albaspina’: This cultivar grows 2 feet tall, with small clusters of white spines. It is hardy in zones 9 to 10. This and other cultivars of O. microdasys are very popular as houseplants. Opunta aurea: Usually known as golden prickly pear, this species grows 9 inches to 2 feet tall and produces yellow flowers in late spring or early summer. It is hardy in zones 5 to 9. This species is popular both as a garden specimen and as a houseplant. The ‘Coombes Winter Glow’ cultivar has magenta flowers. Opuntia fragilis: Known as brittle or fragile prickly pear, this small plant matures to just 6 inches tall and 9 inches wide. True to its common name, it has pads that break off easily, but they also root readily. It grows in zones 4 to 11 and is very popular for outdoor rock gardens or indoor containers. Opunta macrohiza: Known as plains prickly pear, this species grows 6 to 12 inches tall and produces light yellow flowers with red eyes in June and July. It is hardy in zones 3 to 9. It is popular for rock gardens and as a houseplant.
Some species are primarily outdoor plants for southern gardens only:
Opuntia santarita: Known as Santa Rita prickly pear, this is one of the most attractive species, with pads that shift between light blue-gray and rich purple and large yellow flowers that appear in spring. It can grow to 8 feet tall and wide, and it’s hardy in zones 7 to 11.Opuntia aciculata: Referred to as chenille prickly pear, old man’s whiskers, and cowboy’s red whiskers, this ornamental cactus is known for its yellow and red spines and a potential height of 4 feet. It grows in zones 8 to 12.Opuntia basilaris: Also called beavertail prickly pear, this species has velvety pads and deep purple-red flowers. It reaches 36 inches tall and 24 to 30 inches wide and grows in zones 8 to 10.Opuntia rufida: This species grows 6 feet tall; the ‘Purple’ cultivar and has a purplish cast to the pads; it’s hardy in zones 8 to 10.
Pruning
It’s not necessary to prune these cacti for the health of the plants, but you can do it to control the size of the plants—which can a good idea for indoor plants that threaten passers-by with their spines. Hold individual pads with tongs, then cut the pad away along the joint that links it to the rest of the cactus. These removed pads can be rooted to propagate new plants.
Propagating Prickly Pear
Indoors, you can take a cutting to start a new plant at any point during the growing season. You can propagate the plant through cuttings or by seed. To propagate by cuttings:
How to Grow Prickly Pear From Seed
To propagate by seed, cut open a ripe fruit, scoop out some seeds, and rinse the pulp from the seeds. Let them dry thoroughly. Sprinkle the seeds into a pot of moist (not wet) and well-draining potting soil. Lightly cover the seeds with a thin layer of soil or sand. Then, cover the pot in clear plastic wrap, and place it in a warm, sunny spot. Seed germination can take several weeks or even months. Sprouted seedlings can then be transplanted into pots with cactus potting mix.
Potting and Repotting Prickly Pear
When growing prickly pear in containers, choose a pot with generous drainage holes at the bottom. It’s a good idea to choose a low, wide pot to provide a good balance, as these plants will sprawl as they grow. Fill it with a well-draining potting mix, such as one specially made for cactus and succulents. Then, put on thick protective gloves to plant your new prickly pear in its pot. When your prickly pear becomes root-bound or is too large and unstable in its container, only then should you consider repotting. To do so, first, make sure the soil is dry. Then, shimmy the plant away from the pot by grabbing its base and knocking away the old soil. Place it in a slightly larger pot, and backfill with a well-draining potting mix. Don’t water your repotted prickly pear right away; allow it to reintegrate its roots first.
Overwintering
Provided your plant is hardy in your region, no winter protection is necessary. Tender potted plants should be brought indoors when temperatures dip below 50 degrees on a regular basis. Late fall is a good time to trim back your plant, if necessary, to control its size. The removed pads can be used to propagate new plants over the winter.
Common Pests & Plant Diseases
Prickly pear is prone to a variety of insect pests, including scale and mealybug. Treat them with rubbing alcohol, neem oil, or a pesticide. Indoor plants are somewhat more susceptible to pests than outdoor plants. All species in the Opuntia genus can be prone to phyllosticta fungus, which causes lesions in the pads, transitioning to large black spots that scab over. Brought on by wet or humid weather, this fungus is not deadly but it is so contagious that it inevitably spreads to nearby plants. There is no effective treatment—remove and dispose of infected pads to keep the fungus from spreading.
How to Get Prickly Pear to Bloom
Most Opuntia species can take several years before they are mature enough to flower and produce fruit, so it’s possible you just need to be patient. If your plant is quite mature but still is not blooming, remember that it needs plenty of sun, a very porous, dry, soil, and very little organic material or fertilizer in order to bloom. If you are over-tending your plant, it may prevent it from blooming. In rare cases, indoor plants may need just a little fertilizer to prompt blooms.
Common Problems With Prickly Pear
Prickly pear is very easy to grow, and those problems that do occur are usually solved with slight adjustments to care.
Shriveled Pads
If the pads on your cactus (its leaves) are shriveled and dry-looking, it’s likely it’s been underwatered. Water in an increasingly large quantity over several days, just until the pads are plumb and full again. But do not continue watering heavily; excess water is a more severe problem. It’s fine for cactus to be allowed to shrivel slightly in the winter, as it is a natural part of the life cycle.
Pads Are Splitting
If the pads on your cactus are so plump and full that they split, your plant is probably getting too much water. Reduce your watering intervals. Affected pads may need to be removed.
Plant Collapses
A cactus that suddenly sags and collapses is one that has been given too much water for too long. This can cause its shallow roots to rot, causing the plant to collapse. There is usually no recovery from this; the plant will need to be abandoned.
Parts of the Plant are Mushy
If selected parts of the plant or mushy and soft, it’s a warning sign that it is developing rot from too much water. If you reduce watering immediately and cut away rotted areas, you may be able to save the plant. But if rot continues to spread, discard the plant.
Patches of Brown or White
If the pads on your cactus have patches of brown or white, it is probably suffering sunburn from too much direct sun. Move the plant to a location with a bit of shade during the heat of the day. Harvesting the pads involves cutting them off the plant at any time, then carefully removing the spines and hairs. They can be eaten raw, or used in a variety of cooked dishes. The pear-shaped fruits that form along the edges of the pads ripen in later summer and fall; they are ripe when the tiny hairs (glochids) begin to fall off. Once cleaned, they can be squeezed for juice or peeled to eat—the taste is citrusy.
