How to Identify and Fix a Root-Bound Plant

A potted plant you buy at a garden center may look fine but if you take a close look, it is not unusual for the roots to be densely packed in the container. The plant is what’s referred to as root-bound or pot-bound. This is a problem that needs to be corrected before planting; otherwise, the root-bound plant just keeps growing its roots in a tight circular fashion and never sends those roots out into the surrounding soil. The plant’s growth becomes stunted because it never fully established itself and in the worst case, it will eventually choke itself. 

Checking whether a plant is root-bound is quick and easy and saves you time and effort later. If you do end up with a root-bound plant, rest assured, there are ways to fix it.

Identifying a Root-Bound Plant

At the nursery or garden center, before you buy a plant, check it thoroughly. Experienced home gardeners do this all the time when shopping for any type of plants and garden center personnel have no problem with this, provided you don't damage the plant while you inspect it. 

Shrubs and trees are particularly vulnerable to becoming root-bound since they are often grown in pots for several years until they are mature enough to be placed for sale. Especially when investing in expensive trees and shrubs for your landscape, you want to make sure that you don’t bring home a plant with a hidden problem.

1. Turn the plant over and examine the bottom of the container. If you see roots poking through the drainage holes, the plant is likely root-bound. 
2. Next, inspect the root ball by sliding the entire plant out of its container. 
3. Simply grab the plant by its main stem between your thumb and forefinger and lift it up while tugging downward on the pot. You only need to extract a few inches of the root ball to know whether the plant is root-bound. If you see a dense mass of white encircling roots around the edge of the soil, this is not a plant you want to buy. This kind of root ball may easily slide out of the container in a mass of white roots formed into a hard ball. 
4. Disregard any plants that are difficult to remove from the pot, they are likely severely root-bound. 
5. Select plants that reveal a few white roots exposed around the perimeter of the root ball, with plenty of dark soil also visible. The root ball may begin to crumble slightly as you extract the root ball from the container. This is an ideal specimen to buy.

How to Fix a Root-Bound Plant

Hopefully, there are enough choices of a given type of plant for you to inspect several specimens until you find one with the best root structure. If your choice is limited to the one root-bound plant available, there are ways to improve the chances of success in the garden.

Untangle the Roots Before Planting

You can start to help the plant recover by untangling the roots with your fingers before planting. If you tease the root ball into a loose bundle of hair-like roots bristling out from the plant, these roots will more easily find their way into the surrounding soil once you plant the specimen in your garden.

Cut Slits in the Root Ball

If the roots resist untangling by hand, follow these steps:

1. Cut slits into the root ball with a knife or sharp garden trowel. Most plants are quite tough, and by severing the roots you make it easier for the plant to send new roots out into the surrounding garden soil. Some gardeners routinely slice the root ball whenever planting a specimen, no matter if it is a mature shrub in a gallon container or annuals in a bedding six-pack.
2. Make a series of vertical slits along the sides, then slice a deep X in the bottom surface of the root ball before planting.
3. With small six-pack plants, it's usually enough just to slightly tear at the root ball with your fingers before you plant each one.