Method - Highbush Blueberries
Choice and site preparation
Highbush blueberries are of limited hardiness; fruit bud do not survive temperatures below -32°C. Good orchard sites on hillsides are generally well suited.
Limited success can also be achieved on colder sites with wind protection where snow will accumulate. Shorter plants will fruit on the lower 65 cm but will require appropriate pruning.
Blueberries require different soil characteristics for best growth and fruiting. Plant only on light, acid (ideal pH 4.8) soils although organic amendments will improve soil conditions. Before planting, if the soil needs improvement, make a trench along the rows and fill with peat moss. Mix in the top 10 cm of soil with a rotovator. If surface drainage of the site is questionable, apply the peat moss on top and mix so as to end up with a raised bed.
Planting and cultivation
Space plants 1.3-1.5 m in rows spaced 2.5-3.0 m. For best fruit size, use at least 3 varieties. Set plants so as the cover the first 5-8 cm of stems. Irrigate thoroughly after planting and as required thereafter.
Blueberries are well adapted to poor soils and are often damaged by excess fertilization. Do not fertilize at planting but 2 weeks later. For small plantings, use Acid-Gro or other fertilizers for acid loving plants. Commercial plantings can be fertilized with 25 g per plant of ammonium sulfate (21-0-0) spread in a 60 cm circle around each plant. Repeat every 2-3 weeks (but not later than early July) particularly if sawdust mulch is used. Fertilize from late-April and increase rates in the following years without exceeding 125 g per plant per year.
Blueberries do not tolerate a lack of or an excess of soil moisture. Sawdust mulch to a depth of 5-8 cm is often beneficial to blueberries.
Remove flower clusters for the first 2 seasons particularly for weak plants. After 3-4 years, spring prune to remove older, twiggy wood at the soil line. For best quality fruit, pick once per week.
Consult Blueberries - comparative table for a detailed description of varieties.