Raspberries have a fibrous, long-lived perennial root system. These roots are fairly shallow with over 70 per cent found in the upper 25 centimetres of soil. They don’t tolerate poor drainage or excessive cultivation. Suckers are usually initiated in the fall, when they grow only to the soil surface. Additional above-ground growth of the suckers occurs the following spring. There are two types of canes. Vigorous, more productive ones are produced from the crown at the base of the plant and should be kept. Smaller, less productive canes, produced randomly from the roots (further from the established row), should be removed.