University of Maryland Extension

Blueberry Care

blueberry shrubs

Mulching and Watering Blueberries

Mulch and irrigation are essential for fast establishment, steady growth, and consistently high yields. Blueberry plants require at least one inch of water per week (65 gals./100 sq. ft.). You must supplement rainfall when necessary.

Overhead (sprinkler) irrigation can be used on blueberries, but trickle or drip irrigation is preferred because it conserves moisture and does not wet the foliage. The trickle line can be placed directly under the mulch. Overhead irrigation has the advantage of cooling the plants and the berries during extremely high temperatures.

Pine bark mulch, rotted sawdust, and compost are good mulches. Apply them to a depth of 2 - 3 inches and replenish whenever necessary. Avoid mulch with high pH, such as mushroom compost.

Fertilizing Blueberries
CropSoil pH1st Year2nd Year3rd Year and older
varieties of
4.3 - 5.3None

2 oz. of 21-0-0
(ammonium sulfate) per 
during bloom, and 
the same amount
3 weeks 
later. Scatter in a ring
15 in. - 
18 in. from plant. 

Increase by 1 oz. per
year until the 6th year;
then use 8 oz. per
plant each succeeding
year. Avoid fertilizers
containing nitrates or chlorides

Fertilizer - Organic/Inorganic

Harvesting Blueberries

A mature blueberry plant will produce 6 to 8 pounds (7 to 9 pints) of fruit per year. Harvest begins in June and may continue through mid-September with late varieties. Berries turn blue 3 to 4 days before they attain maximum sweetness and flavor. They should be picked every 7 to 10 days. Do not pick berries with a reddish tinge, since they are under ripe and do not ripen after picking. Gently twist the fruit as berries ready to be picked will detach easily from the pedicel (fruit stalk).

Blueberries, like other fruits, should be picked in the morning after the dew has evaporated. If picked in the afternoon, the berries will contain field heat, which will reduce storage life.

Spray Schedule for Blueberries

Of all the fruit crops recommended for the home garden, blueberries require the least use of pesticides. For this reason, treatments recommended for various times during the season should not be applied unless a specific pest problem develops. It is not at all unusual for blueberries to remain relatively pest free for 5 to 8 years or longer after planting.


Additional Resources



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