Blueberries are wonderful plants. Not only do they live for decades and bear delicious fruits that are need almost no care, but they also are beautiful in themselves, with white, bell like flowers in spring and hand some oval leaves that turn orange scarlet in fall. The berries are pretty, ripening slowly so that clusters are green, red and blue all at once. Even the bare reddish stems are eye-catching in winter. I often use blueberries in landscaping a home whether the owners want to eat the berries or not if they don’t certainly the birds will. The plants look good as hedges, at the edge of a pond or even near the house as specimen shrubs.
There’re many different blueberry species. The one most commonly grown for fruit and for ornament is high bush blueberry (vaccinium corymbosum). It is hardiest of the lot and usually grows to about eight feet tall if unpruned but sometimes twice that. Low bush blueberry (V. angustifolium) stays under two feet tall and makes a fine ground cover. Rabbit-eye blueberry (v.ashei) is highbush species that unlike V.corymbosum, does not need to be thoroughly chilled in winter and will bear will in the south. It does not thrive north of Zone 7. V.ashei is a very tall, vigorous shrub that ripens later than northern blueberries; the fruits are generally not as sweet but are large and good for baking. In Connecticut, both highbush and lowbush blueberries grow wild. The wild berries are best of all if you judge by flavor, even though they’re smaller and picking a pie, may take hours. But what better way to spend a few summer hours on a sun baked hillside. The next question is to select the site for blueberry.
Select a Site
Selecting a blueberry site by observing the plants in the wild can be misleading. The highbush ones often grow in swamps, and while it may look as if they’re growing with their feet in the water, they’re actually perched above it, with the ground they grow in soaking up water from below. The lowbush blueberries appear to scramble over bare, rocky mountaintops where there seems to be hardly any soil at all, let alone water. But their long roots are actually snaking down into fissures in the rocks, finding both. The roots of both highbush and lowbush blueberries spread vigorously underground. You should give your blueberries a site where moisture is ample but doesn’t just sit around the roots. Other important factors are full sun so they’ll ripen, and good air circulation to prevent disease.
Select a Soil
Soil should be loose and light but the most important factor in growing blueberries is acidity. Blueberries like a pH of about 4.5 and will grow in anything from 3.5 to 5.5. If you’re not sure whether the soil is acid enough in your area or in the spot where you want to grow them, has it tested. If the soil is alkaline you may want to grow something else instead, but if you’re hell bent on blueberries there’re ways to make your soil more acid. You can add aluminum sulfate purchased from a garden center, following the directions on the package or the recommendations of your soil test, but in most cases you can lower pH simply by digging a lot of acidic organic matter into the soil; rotted leaves, wood chips, peat moss, shredded bark, sawdust any of these will do the trick and will also help the soil to retain the moisture that blueberries need.
Buy dormant plants that are two or three years old those any older are difficult to transplant. You can order them by mail or pick them up locally. Planting bare root is fine and gives you a chance to see whether the plants have a good, healthy, fibrous root system rather than just a few stringy roots. But be sure to keep the roots moist up until the time they go into the ground this is extremely crucial.
Planting blueberries in early spring in cool climates, late fall in mild ones; in holes 18 inches deep and equally wide, well enriched with organic matter. If the planting area has poor soil, enrich it throughout. Don’t add fertilizer or manure directly to the hole, however, though you may spread some on the soil surface. Especially for rabbit eyes so the whole bush can be sun ripened but if you are making a hedge, and then three to four feet apart is acceptable. Dwarf highbush varieties can also go this close, or they can be planted in containers. Well, plant lowbush berries about two feet apart. These can be dug from the wild if you have a source, by removing large pieces of sod along with the bushes. Though planting blueberries at the same depth at which they were growing previously or an inch or so deeper, spreading the roots out in the soil, firming lightly and watering well. Cut back the tops by half and apply a thick mulch almost six inches is about right of an acidic organic material such as shredded bark.
It is very important to keep the plants moist the first year they’re growing and any time that fruit is forming. They should be fed fairly heavily each year at blossom time by top dressing with acidic compost, well-rotted manure, or a commercial fertilizer designed for acid loving plants such as azaleas. You can also use cottonseed meal, blood meal, fish meal, ammonium sulfate, rock phosphate, bone meal or just about anything else you like except materials such as a wood ashes or lime, that will raise the pH. And don’t fertilize excessively with nitrogen or you may get vigorous plants with sparse fruit. However; you can feed again as fruits are forming, but don’t feed past June in climates where late new growth may be winterkilled. Don’t try to dig fertilizers into the soil since the plants are shallow rooted; just remove the mulch, apply nutrient to the soil surface, water well, and replace the mulch. The mulch will break down and do its part in acidifying and lightening the soil; add some more each year.
Well, blueberries especially highbush species, benefits from pruning to keep the plants a size you can pick easily to let sun into the bush to ripen fruits and to keep a good supply of fresh new growth coming along. Berries develop on fruiting spurs produced the previous season on side branches of old main stems. You perhaps won’t have to start pruning until bushes are three to four years old, but make sure then start thinning them once a year while they are dormant. Just when they are about to leaf out is a good time because you can then remove any winterkilled wood. Thin out old, gray canes with lots of little twigs that have grown beyond bearing age and have no fruiting buds visible, cutting them at the base of the plant. Favor the newer, redder canes, keeping 6 to 8 good bearing canes on the bush. Tall, straggly canes can be headed back, and weak, short, twiggy growth can be removed from tips. Note, while pruning, that fruiting buds are fatter than leaf buds; avoid removing twigs with a lot of these.
Pets and Disease
If you buy healthy bushes and take good care of them you will probably have very little trouble with blueberries. There’re some diseases, but most modern cultivars have been bred for resistance. If you live in an area where the berries are more disease prone, apply fresh mulch each year, prune out debris promptly disinfecting your clippers between cuts and go easy on the fertilizer. If bushes succumb to botrytis in wet weather the berries shrivel and the tips die or stunt diseases which are spread by leafhoppers and stunt the plants, destroy them and start over in a new place. They might occasionally get yellows disease if drainage is poor and the pH too high. Mummy berry, a fungus that makes the berries shrivel and harden is often caused by wet weather and poor air circulation. Remove all debris, especially dead berries hold off on fertilizer and turn over or replace the mulch in early spring.
The most troublesome pests of blueberries you’ll perhaps have to cover the bushes with plastic netting or cheesecloth extending clear down to the ground to avoid losing much of your crop. Spreading the netting on a light weight metal or wooden frame work with a flap you can lift to enter the cage will make picking easier. Other pests include blueberry maggot the larva of the blueberry fruit fly, which enters the fruit and rots it. Clean up dropped berries and fight the critter by catching it in the fly stage with yellow sticky traps or by using rotenone. If blueberry stem borers get into the stems in early summer, causing them to wilt, remove the stems and burn them. Pick off Japanese beetles or use milky spore disease.
If you can bring yourself to do it, you should rub off developing berries on young plants until they’re three to four years old, to let the bush put its energy into growth. You’ll start to get abundant crops when the bushes are about five years old probably about six quarts per bush. You should pick at least twice a week, just rubbing your thumb over the berry cluster and letting the ripe berries that look blue are not always ripe. They should really sit on the bush for a week after they are blue, until they fall off easily. The fact that the clusters ripen a little at a time means that you can pick from a single cluster for up to a month and enjoy the berries over a long period. However if you plant early, middle and late varieties you can harvest berries from June to September.
Most blueberry varieties do not self-pollinate well, so it is best to plant several. Though popular early varieties include “Earliblue” the short growing “Northland” and “Collins” which bears in long, uniformly ripening clusters For midseason grown “Blueray” “Bluecrop” and “Berkeley” all of which bear abundant crops of large berries. For later berries grow “Jersey” the shrub is especially handsome, the sweet, dark “Herbert” and to wind up the season, “Coville”. Good varieties for the north are “Northland” “Eariblue” Blueray the early “Patriot” the late bearing “Elliott and “Northblue” which is a self fertile dwarf variety. Tophat is a hardy dwarf that can be grown in tubs. For rabbit eye varieties the standard favorite is “Tifblue”, a vigorous, upright bush that bears fairly late. For an early one try “Climax” or the lower growing “Woodward”. Moreover for midseason try the compact “Southland” and for late seson the sweet-tasting “Delite”.