KNIGHT RIDDER NEWSPAPERS
CHICAGO -- There's a shrub that bears dainty bell-shaped white blooms in May that turn into juicy, flavorful, irresistible fruits in July, perfect for pies, tarts, cobblers, compotes and just gobbling by the handful. In fall, the foliage turns a red that can put a burning bush to shame.
"They kind of glow," said Emily Hoover, professor of horticulture at the University of Minnesota-Twin Cities and fruit extension specialist.
There are kinds that grow taller than a man is, and low-growing kinds that make a lovely ground cover. There are even some that will fit in pots.
What's this marvelous plant? It's one you've known all your life: the blueberry.
The blueberry is native to North America, and the kinds in cultivation are not that far from their wild ancestors. Dan Hartmann, president of Hartmann's Plant Co. in Lacota, Mich., said his nursery sells some plants from cuttings collected in the wild.
There are three main kinds of blueberries: high-bush (Vaccinium corymbosum), low-bush (Vaccinium angustifolium) and half-high hybrids. The largest high-bush types grow up to 12 feet high, Hoover says, though they can be kept smaller by pruning and many are only 5 to 7 feet high. Low-bush are 1- to 2-feet-high scramblers. Half-high cultivars are a mix of the two, most bred to be 3 or 4 feet in height.
Cultivars have been developed for different fruiting times, so if you plant several, you can have blueberries for a long season. Lee Reich, garden writer, serious blueberry lover and author of "Uncommon Fruits for Every Garden" (Timber Press, 308 pages, $24.95), has 10 kinds in his high-bush patch in New Paltz, N.Y. It's a good idea to plant at least two cultivars so they can cross-pollinate for a better yield of fruit.
Things to consider
The most important thing about planting blueberries is preparing the soil, Reich says. First, get a soil test to see where you are. Chances are the test will show your soil is somewhat alkaline, well above the 4 to 5 on the pH scale that blueberries prefer. You will need to add ammonium sulfate -- available in various products at garden centers -- to make the soil more acidic, following the package directions. Amend the entire planting area, allowing plenty of room for the bushes' shallow roots to roam.
Drainage also is an issue. Jenifer Leskawa, public relations coordinator for Stark Bro's Nurseries & amp; Orchards Co. in Louisiana, Mo., says you don't want your plants' roots to rot or suffocate, as they may if trapped in moisture by heavy clay soil. It may be best to plant blueberries in mounds of soil enriched with organic matter and perhaps some sand.
In early spring, "dig a very large hole," says Hoover, allowing for the size that your bush's roots will spread to. Mix the backfill soil with plenty of peat moss, which is somewhat acidic and also adds humus to the soil and holds moisture. Plant your bushes (potted plants are best), and water and mulch the planting area well.
Blueberries produce the best fruit yield in full sun. That makes it harder to keep moisture within reach of their roots, most of which are just under the surface of the soil. Good mulch is essential.
Disease or insect problems are rare. "The major test of blueberries is birds," who love them as much as we do, Reich says. He grows his high-bush patch inside a wood-framed cage of plastic netting; he only puts the top on when the fruits are ripening.
Growing small cultivars of low-bush blueberries in pots might be an easy way to get started in the game, because it allows you to easily control the acidity of the soil and the moisture level. Use a generously sized pot, mulch and be sure to keep the soil under the mulch moist; plants dry out more quickly in pots.
Ornamentally, "I have seen them used elegantly as a long dividing hedge between yards," Hoover says. Blueberries go well with other plants that like acid soil, such as rhododendrons.
There's another benefit to growing blueberries at home, Reich says. The ones you buy in stores or at farmers markets often are a few days shy of being dead ripe because they are easier to pick when they are firmer. If you grow your own, you can pick the fruits at their absolute peak.