Today, more home gardeners find pleasure in growing blueberries in their gardens.
Once given the acid soil they need, blueberries are not difficult to grow and offer many rewards in addition to the delicious berries they produce in the summer.
These include showy white flowers in the spring, vivid scarlet-red foliage in the autumn, and a picturesque habit of growth.
Attractive Highbush Blueberry
Actually, one of the most attractive shrubs for the home garden is the native highbush blueberry (Vaccinium corymbosum), which can be used as a specimen plant, in foundation planting, or as a hedge.
White or pinkish flowers in the spring, lustrous, dense green foliage, a crop of tasty berries, reddish-scarlet fall color, and shiny, red twigs in the winter are some characteristics that make this shrub outstanding.
Highbush blueberry can be grown throughout a wide geographical area of the country.
It is a deciduous shrub that must experience a cold period during the winter to flourish.
It is generally adapted climatically to areas where the apple can be grown successfully.
Widespread Blueberry Cultivation And Development
Among cultivated plants, the blueberry is relatively new. Until about 90 years ago, it was considered primarily a “wild crop.”
Since then, cultivated blueberries have become an important commercial and home garden crop.
A widespread appeal has been stimulated by the development of superior varieties, which are better for their growth habit and more attractive, higher-quality fruits.
Improved varieties, such as Earliblue, Berkeley, Coville, and others, can be expected to produce sizable crops of berries in the third or fourth season after planting for 10 to 20 years.
Mature, well-grown plants may be expected to yield 16 or more pints of fruit each year.
Simple Blueberry Culture
Ideal Soil Conditions
The culture of blueberries is relatively simple if plants are grown on the soil naturally suited to their needs.
The proper soil is relatively acid (pH 4.8 is considered optimum), high in organic matter, and well supplied with moisture.
Unfortunately, few home gardens have this kind of soil, but with a little effort, blueberries will grow on most soils that have good drainage and are not too alkaline.
Planting time is in the early fall, as soon as dormant plants are available, or early spring.
One- or two-year-old plants are best, and because of the ultimate size and long life of blueberries, space about 5’ to 6’ feet apart.
If planning on several rows, allow 10’ feet between the rows.
Although it is not necessary to prepare the soil, working in a small amount of sawdust or peat moss is beneficial before setting out the plants.
Because of the nature of their root system, take special care to set the plants at the proper depth, which is the same as in the nursery, never deeper.
If set too deep, plants will not grow satisfactorily.
As soon as they are set out with organic material, Mulch is applied to an area at least 2’ feet in diameter around the base of each plant. In the row system, spread the mulch out along the rows.
To suppress weed growth, make the mulch thick enough, and once it is established, continue to maintain it.
This can best be done by adding more mulch each year, preferably in late fall.
Excellent Mulching Materials And Their Advantages
Several materials can be used as mulch.
Sawdust, one of the best, may be used either fresh or weathered from either hard or soft wood.
Contrary to popular belief, sawdust has no marked effect on the soil reaction or pH. However, the bacteria in the soil do use up the nitrogen, so adding additional nitrogen is advisable.
If sawdust is unavailable, marsh hay, straw, peat moss, ground corn cobs, buckwheat hulls, pine needles, or any other similar organic material is satisfactory.
Among the many advantages of a mulch are the following:
- It helps to conserve soil moisture
- It keeps down weeds
- It eliminates the need for frequent cultivation
- It offers a better routing medium for the plants
All these benefits result in greatly increased yields and berry size, and one study, covering six years, showed that sawdust mulched plants produced one and one-half times more fruit than unmulched ones.
Another advantage of sawdust, especially for the home gardener, is its attractive appearance.
Fertilizer Applications
Blueberries respond vigorously to fertilizer applications, particularly those high in nitrogen.
Upland soils apparently supply ample quantities of the major fertilizer elements except for nitrogen.
In these soils, blueberries utilize the ammonium form of nitrogen more readily than the nitrate form.
On soils with a pH above 5.0, ammonium sulfate is recommended as a nitrogen source.
In addition, its sulfate radical tends to lower the soil pH toward a more desirable range.
The proper amount to use depends upon the age of the plant.
On mulched plantings, give young plants one-quarter of a pound, but as plants mature, increase the amount gradually until each plant receives approximately a half pound per season.
Fertilizer is best applied in early spring before growth starts.
Broadcast on an area slightly larger than the spread of the branches, but since ammonium sulfate is readily soluble, it need not be worked into the soil.
Where soils are relatively acid, below pH 5.0, any form of nitrogen is satisfactory for soil micro-organisms to convert the nitrate form to the ammonium form.
An occasional application of a complete fertilizer, such as 5-10-5, is desirable on light soils.
Blueberries’ Main Problems
One of the main problems home gardeners have encountered with blueberries on upland-type soils is a chlorotic condition or yellowing of the leaves.
In addition to affecting leaf color, it causes weak, dwarf, and unproductive plants. In severe cases, or where the condition is allowed to persist, death may result.
This chlorotic condition, associated with a deficiency of iron, is apparently due to the inability of the blueberry to utilize iron, though it is present in the soil.
It is common to see blueberry plants suffering from a severe iron deficiency, while other plants growing in the same soil show no signs of it whatsoever.
This problem and the difficulty of combatting it have limited blueberry production on upland soils.
A solution to this difficult problem was realized in 1950 when specially formulated iron-containing compounds, known as iron chelates, became available for agricultural use.
These compounds, readily obtainable from garden supply houses, offer an easy, rapid and long-term solution to the chlorosis problem.
One to three ounces of a chatted iron compound, worked into the soil surface beneath a severely affected plant, will correct all visual symptoms within about 30 days.
Plants so treated will be free of ciliumsis for 2 to 3 years.
In many cases where plants are growing on upland soil, applications of chelates have been beneficial even though marked symptoms were not evident.
Since there are several different formulations of iron chelates on the market, the grower must carefully follow the manufacturer’s directions on the container.
In some instances, foliage applications of chelates are recommended for even quicker results.
Annual Pruning For Excellent Berries
Annual pruning is essential since well-pruned plants are more productive and attractive and have larger berries.
A blueberry plant produces large fruit buds on the young twigs, while below these buds, on the same twigs, are the smaller leaf buds.
During the first and second years after planting, cut off all flower buds to encourage larger, more productive plants in future years.
As the plants mature, however, allow some flower buds to remain.
On established plants, remove sonic flower buds each spring to maintain large berry size, regular production, and healthy growth.
Since the best fruit appears on the most vigorous fruiting wood, eliminate weak, short, and slender twigs.
When a very heavy bud set occurs, head back the most vigorous fruiting twigs by partially removing the flower buds.
44659 by Robert G. Hill, Jr.