Small trees are generally considered those that grow to a height of approximately 30 feet or less, so the process of buying planters for them varies. They are large enough to offer an attractive addition to a yard, but small enough so they won't overwhelm a garden, home, patio or other area. Choosing the right planter for growing a small tree requires that you consider several factors. Depending on how big the tree will grow and if you'll be transplanting it to your yard, you'll need to think about watering, pruning, moving and removing it from the container. With a little forethought and planning, you should have no problem buying the right planter for growing your tree.
Unlike miniature trees, like the tiny bonsai tree that often grows no larger than your forearm, outdoor trees that dozens of feet high but not so wide they hide a home or other structure. Depending on the eventual size of the tree you are planting and how long you plan to leave it in the planter, you may need to choose a more functional, rather than decorative container. A bonsai tree, for example, has a small root system and does well in a shallow container. Growers of these decorative trees often display them in ceramic, tray-like planters. A small tree such as a Japanese maple, citrus or flowering cherry will need a wider, deeper pot-like planter.
Using a larger planter prevents the tree from becoming "rootbound," which occurs when roots don't have enough room to grow outward. The roots begin to grow inward, around themselves in a smaller planter, preventing future roots from growing out and anchoring and feeding the plant. Even if you use a large container, you may experience some root entanglement, so it's a good idea to separate roots prior to planting. For trees you'll be transplanting later, small tree expert Fred Hoffman suggests using a container the size of half a barrel.
Trees grown in containers need more water than those grown in soil because the compost or other material you use in the pot dries out more quickly than dirt. Since roots can't grow outward to find water, you'll need to keep your potting material damp. This may require good soakings that might result in over watering. In this case, your planter should have some form of drainage to let excess water leave the soil and root area. You, or someone you ask to tend the tree, may accidentally over water, or if the tree is growing outdoors, it may be subject to heavy rains. If the planter has a hole in the bottom, keep it off the ground to let water drain; or consider a planter with holes on the side, near the bottom. If your plant will be indoors or you can otherwise control the amount of water it gets, you may not want a planter that drains.
You may be able to more easily transplant your trees if your container is disposable and you can cut or break it, rather than having to pull the rootball out of the container. The less you have to handle and disturb roots, the better. Since you'll want to disturb container-grown roots just before planting to help them spread, it's better not to have to pry or rip the tree out of your planter with an upward pull.
If you plan on keeping your trees in a planter, you'll still need to plan for removal, since you'll need to re-pot them every few years to replenish soil and compost that's had its nutrients absorbed by the trees. This will also help prevent rootbound, giving you a chance to spread the roots.
Whether you plan on starting your small trees in planters or keeping them in containers throughout their lifetime, you can use planters as decorative items to enhance your indoor or outdoor growing space. If your garden has a theme, match the planters to your style. If color is important, buy planters you can paint to match your color scheme. rowing a pot in a planter that's too small can damage a tree; you can solve the problem using attractive oversized planters to dress up a space.
You may need to move the tree from time to time, for watering or pruning. You may also need to move the tree or trees when it's time to transplant them, at which time they'll be heavier than when you started them. Consider placing your planters on some type of dolly so you can easily move them. If you will be moving a heavy dolly over soft or wet ground, make sure it has wheels and an axle system that ensure you can move it with ease!