Blueberries are in the same family as azaleas and rhododendrons. These plants do not have a dominant tap root nor does the root system send down deep penetrating roots. In an ideal situation, this creates a shallow (roughly 6 – 12 inches) root zone. In well drained and aerated soils, it is possible for the roots to reach much deeper. Blueberries grow well in acid soils with a pH of about 4.0 to 5.5. Blueberries will grow in shade or full sun.
SITE AND SOIL PREPARATION: Because blueberries have a shallow root system, only the top 6 – 12 inches of soil needs to be prepared. The area should be well-drained. There should be no standing water, nor should the area be subject to standing water, even during times of maximum rains. Excess water should be able to drain away from the plants within a few hours. Blueberries will not tolerate standing water.
SPACING AND PLANTING: Spacing within a row may average from 3 – 6 feet, dependent upon personal preference. Three feet will give a high density planting and form a hedge quickly, 5 – 6 feet is the average distance between plants. Plants can also be grouped, separated as singles or planted within almost any landscape configuration. The best time to plant blueberry plants is during the winter months, from November to early Spring time.
Prepare a hole about 2 feet diameter and about 8 inches deep. If the dirt appears to be poor, try to have some good potting soil/compost to supplement the soil removed from the hole. Fill the hole about ½ full with this mix of loose soil. If the plant is in a pot, it should be removed and the roots should be fanned out horizontally. This is accomplished by shaking or dipping the roots in a bucket of water and washing the soil from the roots. Place the plant in the hole and fan into a flat configuration.
Do not let the roots dry out, freeze or be exposed to ultraviolet light during this process. Sunlight will kill the small fibrous roots. Roots should be kept wrapped or covered with a damp covering until planted. Place the plant in the hole and fan the roots out in all directions. While holding the plant trunk upright, rake 3 – 4 inches of soil back over the roots and pack by stepping on. Wet the soil to allow the soil to settle around the roots. Do not fertilize at this time of planting.
WATER: The root zone area should always be kept moist – but not too wet! A top mulch of 1 – 4 inches over the root zone is encouraged to conserve water and control weeds. Since blueberry plant roots are shallow, weeds are a major threat. Mulch can be leaves, pine needles, hay, or bark. During the summer, the blueberry plants need about 1- inch of rainfall per week, depending on the soil. The major reason for blueberry plant failure is either too little water or too much water.
FERTILIZERS: Fertilizers formulated for azaleas and rhododendrons are usually ideal for blueberries. Blueberries can tolerate only small amounts of nitrogen at a time, but this important nutrient is required at all stages of growth for healthy development. Fertilize in small amounts or with a specially formulated slow release fertilizer no greater than 10-10-10. Best time to fertilize is right before or during the change from bud to bloom and soon after fruit harvest in late summer.