Raspberries (Rubus spp.) Supply nutrients like vitamins C and A, antioxidants and several minerals in addition to luscious flavor and texture, but they are generally pricey in the market. So growing your own raspberries makes good sense. Various cultivars thrive in U.S. Department of Agriculture plant hardiness zones 3 through 10. Raspberries come in an astonishing array of colors, including black, red, purple, gold and white. Some raspberry varieties only bear fruit for a month in the summertime, while everbearing varieties make strawberries summer through fall. Insect pest bother raspberries less than a number of different kinds of fruits, but a few only can’t resist.
Fruit Flies
A tiny vinegar or vegetable fly with red eyes, the spotted-wing drosophila, preys on undamaged, soft-fleshed fruit, like rasperries, strawberries and plums, unlike its relatives, which favor rotting or fermented fruit. Distinguishing marks on adult males of the species are black spots on the tip of each wing. Spawning as many as ten generations in one year, the short-lived flies become active between the temperature range of 68 to 86 degrees Fahrenheit. Raspberries are prone to attack when they’ve reached their mature color and developed some sugar. UC IPM Online recommends a sugar and yeast water bait for your spotted-wing drosophila: Mix 1 1/2 cups of water using 1/4 oz baker’s yeast and 4 teaspoons of sugar. Let the solution sit for about a day so that it can ferment. Drill four 7/16-inch-diameter holes drilled into the lid of a jar. Then pour the solution into the jar. Hang each jar in a shady place near the strawberries. The flies will input, and most will drown. Assess each week and eliminate dead flies. The solution lasts “several weeks,” according to UC IPM. Good sanitation in the raspberry field will assist in preventing eggs and larvae of the vinegar flies from growing.
Sap Beetles
At about 1/4-inch in length, sap beetles are bigger than fruit flies. Sap beetles are black with yellow-to-orange stains over the backs of the wings. Also referred to as picnic beetles, they bore into ripe or overripe berries to feed. As they are not effectively controlled with any chemical or biological applications, sanitation in the area is essential. Harvest the raspberries as soon as they ripen, so the sight and scent of ripe, rotting or fermenting fruit does not attract them. Clean up all debris after harvest
Additional Berry-Eating Bugs
Another insect pest not easily controlled, the tarnished plant bug feeds on young berries and blooms. Just about 1/4 inch long, the bug has a flattened, oval, copper-brown body.Tarnished plant bugs breed in corn and hay fields, so avoid planting close these plants near raspberry sites. The fruit worm, another raspberry enemy, eats the buds and strawberries. In smallish infestations, fruit worms can be picked off. Cultivate around the plants during late summer or early fall to expose that the worms to their predators and stop them from overwintering as pupae in the ground. Cornell University horticulturists crossed a purple and a red raspberry to create “Royalty,” a large, sweet variety for USDA zones 4 to 8 that is resistant to fruit worms.
Hungry Birds
Birds often present a problem when they rob your raspberry patch before it is possible to harvest your crop. Foil them by spreading plastic netting over the plants. Or, if this gets in the way when pruning plants or choosing grasses, erect a lightweight support to hold the netting up off the raspberry canes. Construct the frame of timber or metal, either in the shape of a box or slanted like an A-frame house.