Blueberries are native to the Americas.

Highbush blueberries (Vaccinium corymbosum) are the type most likely to be grown in Pennsylvania.

They are large, upright, deciduous shrubs that produce large berries on canes growing from a central crown.

This shrub can be five- to eight-feet-tall and wide at maturity or even larger.

Many cultivars exist and are defined by the time frame that berries ripen: early, early mid season, mid season, mid late season and late season.

While these blueberries are self-pollinating, growing more than one cultivar creates larger berries and crops, so you are rewarded by selecting cultivars that provide ripe berries from late June through September.

The most critical aspect of successfully growing blueberries is siting and soil preparation.

A garden area where rhododendrons and azaleas are thriving is a site where blueberries will thrive, too.

Blueberries prefer a sunny site with moist, porous, acidic soil and an ideal pH between 4.5 and 5.0.

Test your soil and amend it according to recommendations in the early fall for spring planting.

Generally, sulfur is added as iron or ammonium sulfate (not aluminum sulfate, which is toxic to blueberries) and it takes time in warmer weather to work.

Because of the exacting soil requirements, you may opt to build raised bed areas for blueberries.

Some newer cultivars have been developed specifically for containers.

These are useful in small or patio gardens and where amending the soil is problematic.

Find two-year-old potted plants or bare-root plants.

Amend the planting hole with one-half peat moss, which is acidic and provides porosity for better water retention.

Mulch new plantings with four inches of hardwood bark mulch or aged sawdust.

Do not use mushroom manure as it is too alkaline.

Laying soaker hoses under the mulch is useful for easy and adequate watering.

Blueberries have shallow root systems and are sensitive to inconsistent soil moisture.

They need at least one inch of water per week.

A soaker hose will also help reduce the incidence of disease such as anthracnose fruit rot, botrytis blight and fruit rot and leaf rust.

Patience is rewarded with blueberries.

Wait a few years for a harvest.

Remove all flowers for the first two years and up to half the third year.

The plant’s energy will then be focused on cane development.

Fertilize yearly with an all-purpose fertilizer meant for acid-loving plants.

Keep the mulch at four inches.

Pruning is necessary to produce a vigorous plant as it matures.

Once mature, pruning also invigorates the plant by forcing new growth to replace older, less productive canes.

The best time to prune is at the end of the dormant season, usually in March.

A mature high-bush plant produces six to 10 pounds-pints of blueberries.

Berries picked early will be tart and red and will not ripen off the plant.

Wait to harvest until the berries are fully ripe.

Blueberries turn blue three to four days before they are at their sweetest and most flavorful.

Birds love this fruit, and your entire crop may disappear in a day while you are waiting.

Bird netting is helpful as a barrier.

“Growing Green” is contributed by Lehigh County Extension Office Staff and Master Gardeners. Information: Lehigh County Extension Office, 610-391-9840; Northampton County Extension Office, 610-813-6613