When you hear “prickly pear,” you probably think of desert-loving plants full of sharp spikes. But did you know that not all of these cacti live up to their name?
Mostly considered a novelty plant today, spineless cacti were once bred to be a versatile food crop, much like corn. Unfortunately, the thornless cactus got off to a bit of a rough start in the commercial plant world, causing it to fall into obscurity for a time. As such, spineless prickly pears aren’t cultivated nearly as much as their thorny counterparts, but they’re starting to make a slow comeback as gardeners and farmers recognize their potential as a low-input, high-yield food source.
A Prickly Past
Opuntia, commonly known as “prickly pear,” is a genus of flowering cactus plants in the Cactaceae family. Prickly pears are native to North, Central, and South America, and they’ve been introduced into many other parts of the world, including Africa, Europe, and Australia. A few naturally spineless varieties exist – and were around long before the plant was commercialized – but many prickly pear cacti are covered in long, sharp spines.
Prickly pears are hardy and grow in a wide range of soil conditions and climates. Both the fruit and the pads are edible, and the cacti are even a staple food in some countries. Because they grow abundantly and have excellent nutritional qualities, prickly pears have also been used by farmers and ranchers as a source of food and water for livestock. They grow easily in drought-like conditions, making them an appealing alternative to less-hardy feed sources. To safely feed the spiked cacti to livestock, however, the sharp spines have to be removed through expensive and time-consuming methods.
Looking for a way to remedy the prickly pear’s spiky conundrum, plant breeder Luther Burbank began working in the early 1900s to refine and promote the naturally spineless varieties. Between 1907 and 1925, as a result of years of work on his farm in Santa Rosa, California, Burbank introduced more than 60 new cultivars of spineless cacti. Most of these were hybrids bred from varieties of Mexican prickly pear (Opuntia tuna) and Indian fig (Opuntia ficus-indica).
Unfortunately, Burbank’s spineless cacti met some hurdles early on. After being promoted as desert-loving plants able to thrive on little water, it became clear that the cacti did, in fact, need adequate irrigation to grow well. And although the plants could grow fairly quickly, concern arose that they couldn’t produce food fast enough to be a reliable source of livestock feed, the use for which they were often promoted. Additionally, varieties of naturally spineless cacti existed before Burbank’s plants, leading to distrust and skepticism of Burbank and his marketing. Still, the plants were enthusiastically promoted by the press, and interest from the public grew.
Once the plants were finally available for sale, disaster ensued when a company bought the rights to sell the plant under Burbank’s name. Interest in the spineless cacti was high, and the demand grew so large that the company wasn’t able to produce enough plants. Nevertheless, salespeople were instructed to accept every order. When supply ran out, the Luther Burbank Company bought ordinary prickly pears and, after removing the spines, sold them as spineless cultivars to fill the orders. Eventually, the fraud was uncovered when the pads produced fully spined cacti. As a result, the company went bankrupt, and interest in spineless cacti faded as corn became a popular alternative.
Cultivating Spineless Cacti
Despite their thorny history, spineless prickly pears are still around today and remain a viable food option for both humans and livestock. One specimen can provide enough pads and fruit for the table, while a bigger planting can be a great source of drought-tolerant fodder or provide a marketable amount of fruits and pads.
Soil preparation and planting. Spineless cacti grow best in a climate with sunny, warm summers and cool, dry winters with an annual rainfall between 12 and 24 inches. Many are hardy to 23 degrees Fahrenheit, and some cultivars can withstand even lower temperatures.
You can start the cacti from seeds, but it’s much easier to use cuttings from the pads, which readily give root. The best time to start spineless cacti outdoors is in spring or summer, or you can start them in a greenhouse at any time. You can purchase spineless cactus pads from a nursery (don’t worry, they’re not counterfeit anymore) or take them from an existing plant. If you have trouble finding a cutting, ask around to see if you can get one from a friend or local gardener. If you take pads from an established plant, select fresh, green pads that are 6 months or older. Wear gloves and long sleeves while handling the cacti, because while they don’t have sharp spines, they may still have small glochids that can be a nuisance. (Glochids are tiny hair-like bristles that grow on the plant.) Using a sharp, sterile knife, cut pads off at the base, where they attach to the parent plant. Leave cuttings to dry for several weeks in a shaded, well-ventilated area so they form a callous on the cut end.
Spineless cacti can be grown in a wide range of soil conditions, but you’ll want to avoid waterlogged soil or heavy clay soil. If possible, select a sunny spot with gritty or loamy soil that drains well. Prepare the site before planting by working the soil to a depth of 20 inches and removing all weeds. Incorporate a fresh application of compost or well-composted manure into the soil.
Plant pads upright so one-third of the pad is in the soil. Orient the slim side north to south to help protect young cuttings from the midday sun while they receive the more beneficial morning and evening rays. Support the cuttings with a stake or a few stones. If you’re planting multiple plants, arrange them in rows running north to south. How far apart you space the cuttings will depend on how much time you want to dedicate to caring for your plants. Spacing them closely together will result in significantly higher yields (because there will be more fertile pads clustered in one area), but the plants will require more care. Generally, plan on 31⁄3 feet between pads and 13 feet between rows. If you don’t want to prune your plants regularly, space them farther apart. The cacti will start to produce pads for harvest after several months, and flowers and fruit will appear after 2 to 3 years.
Watering. Once planted, the cuttings will use the moisture stored inside them to grow, so they won’t need immediate watering. Water the pads only after they’ve formed roots and can stand on their own without support – about one month after planting. Once established, spineless cacti can survive on rainwater alone, although they’ll produce more pads and fruit when watered regularly. Water every two weeks in summer and once a month during the rest of the year. Let the soil dry up between waterings. With good drainage, spineless cacti can tolerate quite a lot of water.
Fertilizing. If you’re growing your spineless cacti for fruit, apply a 0-10-10 fertilizer once a month throughout the year. This will increase productivity. The plants also respond well to organic fertilizers, such as compost or manure. Organic fertilizers are commonly used when the plants are grown for pads instead of fruit. When using an organic fertilizer, apply it every other year. Because water makes the nutrients more readily available, try to plan your fertilizer application around predicted rainfall.
Pruning and thinning. Pruning your spineless cacti will help maximize growth, manage pests and diseases, and increase fruit yield. Generally, the closer the distance between the plants, the more you’ll have to prune. To get a good supply of both new pads and fruit, maintain a steady balance between 1-year-old pads (for fruit and flowers) and 2-year-old pads (for new pad growth). As a general rule, prune to leave no more than two new pads on a parent pad. Prune new pads developing on 1-year-old pads, and prune 2-year-old pads that don’t have new growth. Wait to prune until the temperatures are high enough for the cuts to dry quickly, and always clean and disinfect your pruning tools to avoid spreading fungus and diseases.
During the first two years of growth, your cacti will also benefit from selective pruning to maintain a distinct shape, known as “training.” You can do this by pruning any inward pads or those growing close to the ground, as well as any pads growing downward or horizontally. Cacti are commonly pruned to form a pyramid or globe shape with three or four main stems to encourage light distribution and ease of management.
Spineless cacti can be quite long-lived, although they’ll become less productive 25 to 30 years after planting. Older cacti can be rejuvenated with intensive pruning. To do so, cut them back to a height of 1 to 2 feet, removing any growth that’s 4 to 5 years old or newer. The plants will start producing abundant fruit and pads 2 to 3 years later.
You’ll also need to thin the fruit on your cacti to encourage bigger and more uniform fruit. The best time to do this is 10 to 20 days after flowering. Try to remove the weaker fruitlings while leaving the bigger ones on the pad. The fruits develop best with 9 to 12 fruits per pad.
Weeding. Although it isn’t necessary, regular weeding will ensure a bigger crop of both pads and fruit. Spineless cacti roots grow to about the same depth as most weeds, so they’ll end up competing for nutrients and moisture if you don’t weed around them.
Harvesting Pads and Fruit
Harvest pads when they’re 4 to 8 inches long. Expect a harvest of 2 to 4 pads per plant in the first year. An established plant can yield between 20 and 40 pads each year. Small, young pads harvested in spring are the most succulent and flavorful. Harvest the pads by carefully cutting them off at the joint midmorning, which will ensure the lowest acid content and sweetest taste. The pads can be harvested every 15 to 30 days, but don’t harvest more than one-third of the plant at a time. You can eat pads raw, boiled, grilled, or pickled. They taste similar to green beans and have a crunchy texture, much like okra.
Spineless cacti will start to produce flowers and fruit 2 to 3 years after planting. Before ripening, the fruit will bloom in a variety of colors, including red, yellow, orange, and purple. To harvest the fruit, carefully twist it off the pads after any glochids have fallen off. The deliciously sweet fruits taste similar to melon. As with any crop, yield can vary greatly depending on climate, cultivar, and care, but you can generally expect a mature, well-cared-for cactus to produce up to 200 fruits a year. Undamaged fruit can be stored for up to one month at 68 degrees. Damaged or bruised fruit can also be fed to livestock; it’s a great source of vitamins.
If grown on a large scale under the right conditions, the plants can produce more than 20 tons of dry matter and store 180 tons of water a year per every 21⁄2 acres. Additionally, unlike many other fodder crops, spineless cacti provide fresh fodder year-round, reducing the need for storage. The harvested pads can be cut or chopped and mixed with other livestock feed.
In addition to their edible offerings, spineless cacti pads produce a juice that can be used to help heal wounds and burns, much like aloe. You can also harvest strong fibers from the pads that can be used to make mats, baskets, and fabrics. And if you cut the pads into thin slices and place them in water, they’ll release a mucilage that can be slowly dried in the sun to produce a white-colored gum. One or two large pads will produce a gallon of thick, transparent mucilage. The mucilage can also be used to waterproof and stiffen cloth, and it can be mixed with whitewash, which gives it the permanency of paint. It’s also reported to make an effective natural mosquito repellent when spread over water to smother larvae. These effects have been known to last more than a year.
Pests and Diseases
Spineless cacti aren’t affected by many pests or diseases, except for a few sap-sucking insects and types of rot. As with any plant, prevention is the best treatment. Regular pruning and deadheading will help keep your cacti healthy and insect-free. Don’t leave any pruning waste near the cacti, because it’s a breeding ground for pests. Water carefully to avoid rot and fungus.
If an insect infestation does occur, apply insecticidal soap or horticultural oil. If you choose to use an insecticide, don’t apply it while the cacti are in bloom in order to minimize the chance of harming pollinators. You can also use biological methods to help control cactus pests. Here are a few of the more common pests and diseases you might encounter.
Telltale signs: You’ll notice a white-colored cotton-like mass on the surface of the pads that crushes to a bright-red color.
Control: Blast the affected area with a pressurized hose. Afterward, treat the area with an insecticidal soap or a mix of ½ teaspoon of dish soap per 1 gallon of water. Remove seriously infected pads. Treat severe infestations with a combination of natural insecticide, dormant oil spray, and insecticidal soap.
Cactus Moths and Borers
Telltale signs: The moths lay eggs in stacks that look similar to cactus spines. Once they hatch, you’ll see the larvae (borers), which are creamy pink to orange with reddish-black dots or bands along their backs. They’ll chew large holes in the pads, leaving a pile of shredded cactus flesh nearby.
Control: Inspect cacti regularly for the larvae and egg sticks. Remove and destroy infected pads. Handpick the worms at dusk and drown them in water. Adult moths can be captured with pheromone traps.
Cactus Longhorn Beetle
Telltale signs: You’ll notice holes filled with a black substance. You’ll also see shiny, black, inch-long beetles.
Control: Remove the beetles manually by handpicking them during the early morning or late evening. Neem oil can be used as a repellent.
Rots and Fungus
Telltale signs: You’ll see spots, scabs, and fruiting structures.
Control: Inspect plants regularly, especially after wind, rain, or hail. Avoid overwatering. Remove and destroy infected pads and plants.
Samuel Feldman is a farmer and writer – by both hobby and profession – who’s currently researching new crops and agricultural techniques. His work has been published in multiple publications, including Farming Magazine, Acres U.S.A., and Countryside.