Agriculture Reference
In-Depth Information
drainage before attempting to plant fruit trees on them. We'll cover specific
By digging trenches, you can estimate rooting depth. Ideally, you should
have 5 feet or more of rooting depth for fruit trees and a water table that
remains at least 3 feet below the soil surface. You can certainly grow fruit
trees on shallow soils, but doing so is more challenging than on deeper soils
and may not be suitable for all fruit crops.
The types of vegetation growing on your orchard site will also give
you information about your soil. Cattails, sedges, rushes, reeds, and certain
grasses and other plants that are associated with wetlands or otherwise
poorly drained soil are a giveaway that this location is not a good choice for
an orchard.
Soil pH
Soil pH is usually manageable in most parts of the United States and
Canada. The term pH refers to the soil's acidity or alkalinity, which has a pro-
found influence on the availability of soil nutrients to plants. Soils with pH
values less than 7.0 are acidic, while pH values above 7.0 indicate alkaline
soils. Although an optimum soil pH for fruit trees is between 6.5 and 7.0, pH
values ranging from 5.5 to 7.5 seldom create serious problems for most fruit
tree crops.
Soils that are too acidic are seldom a serious problem for fruit trees be-
cause raising the soil pH with limestone or dolomite is generally straightfor-
ward and relatively inexpensive. Orchard management practices can be de-
vised to help maintain an elevated soil pH.
Excessively alkaline soils are more challenging. As soil pH rises much
above 7.5, fruit trees begin showing symptoms of iron chlorosis and other
nutrient disorders. Yellow to yellowish-white leaves with green veins are the
classic symptoms of iron chlorosis, which also includes stunted growth, poor
yields, and even tree death. While iron chlorosis can be caused by a lack of
iron in the soil, which sometimes occurs on acidic, organic soils, by far the
most common cause is high soil pH. In these cases, iron may be abundant
