Shrubs and trees are sold in 3 ways. Most are grown in plastic or metal containers, or balled and burlapped, or “B & B” stock. B &B plants are grown in the field, dug up, severely root-pruned, and the surviving root systems wrapped in large balls of field soil with burlap to keep the roots moist. To a lesser extent, some shrubs and small trees are sold as bare root stock, in which the plant’s roots have no soil around them but are packed in damp organic material such as sphagnum moss. This method is much favored for mailorder plants and for many types of roses.
Although balled and burlapped plants lose most of their original roots when initially dug up, the flexible burlap and soil ball allows new roots to spread out more naturally, downward and outwards. The B & B technique is favored for many large shrubs and trees over 6 feet tall and for most evergreens. Containers are popular because they are smaller (up to 15 gallons capacity) and don’t weigh nearly as much as a soil ball. More importantly, the root system is intact. Therefore, container plants are less easily damaged in the nursery and they are more likely to withstand transplanting. One drawback to containers is that the plants can become severely rootbound if left to grow in the confined space for too long. With the salesperson’s permission, gently tap the rootball out of a container to check for this. If the roots go round and round, look for another plant, because those roots will continue their dizzying journey in your planting hole, increasing the risk of transplant failure.
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