How to Grow and Care for Eastern Prickly Pear Cactus

Eastern prickly pear, Opuntia humifusa, is a surprisingly simple cactus. It's undemanding to grow, hardy enough to survive in climates down to at least USDA Zone 4a, and boasts a cheery, delicate flower. Native to the eastern United States, the eastern prickly pear cactus doesn’t have the stature of its desert cousin Opuntia ficus-indica (which can top 15 feet), but this smaller version adds a touch of the southwest to cooler climates and makes up for its diminutive size with its hardiness. The cactus can either be started from cuttings in the early summer or from seeds in late spring.

Prickly Pear Care

Eastern prickly pear is an easy-to-care-for cactus, favored by desert dwellers and cool-weather gardeners alike. Its stems are divided into flat paddle-like segments that are approximately two to seven inches long with a blue tint. The narrow spines are wedge-shaped and the flowers, which come into bloom in mid-summer, are a brilliant yellow. East of the Appalachian Mountains, the flowers often have a red or orange center. The flowers are followed by edible purple or red fruits called tunas. These are the prickly pears and, though they're not as large and tasty as the prickly pears of O. ficus-indica, they can be made into nice jellies and pickles.

Prickly pears are a cactus, so they need well-draining soil first and foremost. Plant in full sun in a sandy or gravely mix and go easy on the water. Also, don’t be alarmed if your plants appear to deflate during the winter—this is their normal response to dormancy, and they’ll plump back up in spring.

Light

As with most cacti, the eastern prickly pear does best in full sun for at least eight hours a day. That being said, it can handle partial shade if it's planted in hotter climates, like a more traditional desert landscape. More light exposure will also lead to a larger plant and more blooms come mid-to-late spring and summer.

Soil

For the prickly pear to thrive, it needs to be planted in well-draining soil. Your best bet is a mixture that is dry, sandy, or gravelly, but it can also do well in a mixture that is primarily clay, so long as it drains very well and the soil does not retain much moisture. When it comes to pH levels, prickly pear isn't especially high-maintenance and can thrive in a neutral-to-acidic mixture with a pH level of 6.0–7.5.

Water

As to be expected, the prickly pear cactus is extremely drought tolerant, so when in doubt, water it less than you think it needs. In most areas, the typical rainfall will likely be enough for the cactus to thrive but if not, you can plan to water the plant every two to four weeks.

Temperature and Humidity

Like any cactus, the prickly pear likes warm, dry weather. Though it's more cold-hearty than most other cacti and can survive cold temperatures down to 14 degrees Fahrenheit, it will grow larger (and bloom more) when raised in warm temperatures. Keep in mind, it needs to be kept dry, so any additional humidity (like misting the plant) is unnecessary.

Fertilizer

When planted outdoors in garden soil, no fertilizer is needed. However, occasional feeding may be required indoors. Use a well-balanced fertilizer and let the plant tell you when it needs food—if its green color starts to pale or it doesn’t flower, it should be fed.

Types of Prickly Pear Cactus

In addition to the eastern prickly pear, there are other varietals throughout the United States.

• Beavertail (Opuntia basilaris) : This pink-flowered variety blooms in the spring and is found in native lands up to 8,000 feet of elevation.
• Englemann (Opuntia engelmannii): Known for deep red or purple fruits, this variety has wide-spaced spines.
• Mojave (Opuntia erinacea): The mature plant doesn't offer much in the way of fruit, and grows best at over 3,500 feet of elevation.
• Santa Rita (Opuntia santa-rita): This striking variety offers pads of vibrant blue-gray or purple.
  

Pruning

Pruning is not necessary for the prickly pear cactus, but you can remove a pad from the plant to help it maintain its proper shape. To do so, hold the pad with tongs or a hand covered in a thick glove; cut the pad at the base.

Propagating Prickly Pear Cactus

While you can grow prickly pear from seeds, it can take up to three years to have a substantial plant, so propagation is often the preferred method. To do so, remove an individual pad from the mother cactus that's at least six months old. Allow the cut end to "heal" for at least a week, or until it scabs over. At that point, you can plant the pad cut end down in a mixture of soil and sand. It will likely need to be supported on either side until it grows roots, so use stakes or other supports to hold it upright. After about a month, test for new roots by tugging on them gently—if the plant resists pulling, you have roots. If it comes loose, give it more time. You can water the cactus sporadically after it's able to stand on its own.

Potting and Repotting Prickly Pear Cactus

Prickly pear can be grown in pots until it becomes large enough to need space outdoors. To pot the prickly pear cactus, choose a pot with numerous drainage holes and a potting soil designed for succulents. For even better drainage, start with a layer of gravel at the bottom of the pot.

Start with a pot that is a few inches broader than the largest pad. The cactus can grow in this pot for a season or two; when it becomes rootbound, it's time to move to a larger pot.

Overwintering

When growing a prickly pear cactus in a pot, make sure to bring it indoors during the winter. It should survive just fine in the typical atmosphere of a home during the wintertime. If the cacti are in the ground outside, protect them from the harshest cold with a generous layer of mulch around the bottom of the plant.

Common Pests and Plant Diseases

The most common problem when growing a cactus is giving it too much water, which can cause its shallow, fibrous roots to rot and the cactus to collapse. They're also susceptible to a variety of insect pests, including scale and mealybug, both of which can be treated with rubbing alcohol, neem oil, or, when very serious, a pesticide.

Prickly pear cactus can be afflicted by the phyllosticta fungus. Brought on by tiny spores that colonize the tissue of the cactus when the weather is particularly wet or humid, phyllosticta can eat lesions into the pads of the cactus, eventually causing large black spots that scab over. While not deadly to the prickly pear cactus, phyllosticta is very contagious and can easily spread to neighboring plants through heavy wind or rain. There is no effective treatment for phyllosticta—instead, it's recommended that you dispose of infected pads or cacti to ensure the disease doesn't spread.

How to Get Prickly Pear Cactus to Bloom

Prickly pear cactus might not bloom for the first few years of its life. To help it along in later years, fertilize once a month with a 5-10-10 fertilizer and keep it in the sunniest possible area. When it reaches the point of maturity and begins to set fruit, make a point of cutting the flowers back to about 10 per pad, to encourage plenty of room for growth of the fruit.

From: thespruce