 |
|
|
|
| |
The Garden Plot for May 30, 2008
3:55 PM - 4:00 PM
[Program Website]
Today's Highlight: “Roots”
When planting flower and vegetable starts and seeds, try to think like a root. Understanding how a root grows will make you a better gardener. Roots affect a plant’s size and vigor by adapting to soil types and chemistry, and responding to fertilizers and different irrigation techniques.
During early development, seedlings absorb nutrients and water from the soil directly surrounding the sprouting seed. Compost or slow release fertilizer applied several inches to each side and slightly below newly planted seeds helps early growth of most garden crops.
As a plant becomes well established, the structure, quantity, and distribution of its roots determine its ability to absorb water and nutrients. For most plants, the majority of the feeder roots are located in the top 12 inches of soil. The soil environment in this region generally is best for root growth, with a good balance of fertility, moisture, and air spaces for oxygen.
The ROOT CAP is the root’s outermost tip. It consists of cells that are sloughed off as the root grows through the soil. Its function is to protect the root’s main growing point.
ROOT HAIRS are delicate and occur in a small zone just behind the root’s growing tip. Gardeners seldom see root hairs because when a plant is pulled up, they are broken off. They look like a fine, filamentous down when unbroken. Root hairs absorb water and nutrients which then pass into conducting tissues for transfer above ground. Root hairs usually live one or two days. When a plant is transplanted, they are easily torn off or may dry out in the sun.
The root hairs and the root cap wear off as the root penetrates the soil and are continually being replaced. This area of the root is one of the most active growth areas on the plant. As a result, when plants are young with fewer roots, a high level of available nutrients in the soil is essential. Active growth also requires good quantities of oxygen. Roots in water-saturated soil do not grow well and ultimately may die due to lack of oxygen. Generally roots grow better in drier, rather than wetter, soils. Roots penetrate much deeper in loose, well drained soil than in heavy, poorly drained or compacted soil. A dense, compacted soil layer can restrict, or stop, root growth. In addition to growing downward, roots grow laterally and often extend well beyond a plant’s drip line (the point to which a plants’ leaves extend). Remember when disturbing the soil around existing trees and shrubs, roots may extend 1.5 to 2.5 times the radius of the drip line. Roots take up nutrients differentially and at different rates depending on whether they are in a vegetative (leaf-producing) or reproductive (flower producing) stage of growth. Roots of plants in the leaf-forming stage take up nitrogen faster. So, don’t let young seedlings or transplants run out of nitrogen.
With these root facts in mind, it’s time to dispel a myth about transplanting container plants. If you purchase a plant with a tight mass of roots, do not tear apart the roots. Don’t worry about “root-bound” plants. The active-growing root tips are found at the outside of a root-bound plant. If you can see white, healthy new roots, just add a bit of compost to the planting hole for those roots to easily expand into. Then, water the plant in well and don’t let it dry out for the first month while new roots grow into the soil.
Helen Atthowe's new short program of gardening tips
|
|
|
