Sharpblue is the leading and most adaptable variety in low chill areas throughout the world. Great for milder zones, it requires only 200 chill hours. Sharpblue will bloom and fruit almost year round, with foliage remaining nearly evergreen. Sharpblue is recommended in areas with mild winters where frosts are uncommon. Upright, spreading bush reaching 5'-6' tall with green foliage in fall. Medium, robust flavored berries.
Water blueberry plants during the day. Keep the soil moist but not soggy. Give them at least 1" per week during growing season and up to 4" per week during fruit ripening.
Blueberries prefer full sun, but will tolerate light shade (they may be less productive in shade but will still produce some fruit).
Most fertilizers for container-grown blueberries can work perfectly with the blueberries that grow in soil. Fertilizer with nitrogen in the form of urea or ammonium is perfect for the blueberries that grow in a container. Ammonium sulfate (21-0-0) is among the best nitrogen fertilizer.
For best results, set plants out as early as possible in the spring. Prune branches back about 1/2 their length at planting time with no further pruning required the next 3 years. Prune annually thereafter during the dormant period. 'Sharpblue' blueberries may require protection from the spring frost.
During dormancy, blueberry plants can typically withstand temperatures below 20° F with no injury. As buds expand and develop, the critical temperature where damage can be expected to increase is through the 20s to about 31° F for plants with green fruit.
For blueberry plants, that means opting for the largest pot possible, planting one plant per pot. Choose a container that's at least 18 inches deep and boasts ample drainage holes. Half-barrels and other deep, wide containers work well for keeping blueberry plants in for the long term.