Raspberries are delectable little morsels that are easy to grow and to reproduce. While these plants can be propagated from seeds, they won't grow "true" and there's no telling what you'll end up with. All raspberries can be cloned by simply dividing the mother plant's roots. But if this doesn't suit you, there are alternatives. Raspberry-plant species are loosely divided into two classifications, and they can be propagated by different methods. Red raspberries include all red or yellow varieties and are grown from suckers, or root cuttings. The black-cap class consists of black and purple species, neither of which send out suckers. Instead, they're easily tip layered.
Red Raspberries From Sucker Shoots
Check the bases of your red raspberry plants for new shoots after all danger of frost has passed in early spring. They'll be easy to spot quickly because they're a much lighter color than older canes.
Sever the new shoot from the mother raspberry plant when it's at least 6 to 8 inches tall. By then it will have grown its own healthy root system. Slide a sharp gardening spade between the plant and its shoot vertically, dividing their root systems below the soil line.
Plant the new raspberry shoot in your growing area at the same depth it occupied when growing on the parent. Make sure to give all of your raspberries plenty of room, leaving 3 to 5 feet of space between each.
Water and fertilize the new raspberry plants just as you care for your older plants. Make sure to be extra fussy about keeping them free of weeds, though.
Tip Layering Black-Cap Raspberries
Examine your mature black or purple raspberry plant in late August. By now it should have grown canes that are so long that they droop, and some of the tips might already be touching the ground. These are perfect for tip layering.
Dig a hole 3 to 4 inches deep right about where the plant's tip is touching, or where the cane can be gently bent so that its tip can easily touch the soil.
Poke the tip of the cane straight down into the hole and cover it with soil. At first, the tip will grow downward. But soon, it will bend itself upward sharply, and roots will develop naturally on the bend.
Keep the tip watered so that the soil is evenly moist but not soggy or wet. Soon it will emerge from the soil as a new plant. There's no need to feed it until next year.
Sever the new black raspberry plant from the parent in late fall or early next spring. You can leave it right where it is if there's enough space between it and other plants. Or you can choose to transplant it elsewhere. Treat the tip-layered plant just as you do the other black raspberries. By now it's large and healthy enough that its maintenance requirements are the same as those of older specimens grown in your area.
About this Author
Axl J. Amistaadt began as a part-time amateur freelance writer in 1985, turned professional in 2005 and became a full-time writer in 2007. Amistaadt’s major focus is publishing garden-related material for various websites, specializing in home gardening, horticulture, alternative and home remedies, pets, wildlife, handcrafts, cooking and juvenile science experiments.