Backyard Gardener: Growing beautiful blueberries
Hello Mid-Ohio Valley gardeners and farmers! September has come to a close and cooler weather has finally arrived, along with some needed rain. October, of course, brings falling leaves (which we will compost as leaf mold), college football and amazing sunsets. Many gardeners are finishing final harvest of beans, squash, late plantings of sweet corn and any tomatoes. The dry weather has affected many vegetable gardens as well as cut down on frequency of mowing the lawn. Any green tomatoes can be used for recipes such as green tomato jam, used in place of tomatillos in salsa recipes, or fried for the kitchen favorite fried green tomato sandwich.
Fall can also be a good time to plant trees if we have adequate moisture. Temperatures are usually cooler and there is less weed and insect pressure. Select balled-and-burlapped or container-grown plants rather than bare-rooted stock. Bare-root plants should only be planted in late winter or early spring while the plants are still dormant. Now may be a good time to purchase trees garden centers are motivated to sell because of the expense of keeping them over winter.
The key to planting trees and shrubs in fall is to plant early for developing a good root system. Soil temperatures should be well above 55 degrees at a depth of six inches at planting time. This condition usually exists until early to late October. It is critical how you dig the hole for your new tree. Research shows most of the roots on the trees grow in the upper 12 to 18 inches of soil and spread out two to three times the canopy of the tree. The greatest cause of death of newly planted trees is planting them too deep. Dig a wide, shallow hole two or three times the size of the root ball so the roots can spread out.
It is also important to provide adequate moisture and protect planting trees and shrubs throughout winter. Water plants thoroughly to supply about one inch of water per week and continue watering until the ground is frozen. Applying two to four inch layer of mulch will protect trees and shrubs and can help prevent wide soil temperature fluctuations and reduce heaving by alternate freezing and thawing of the soil that often occurs in winter. Compost, shredded bark mulch, straw and shredded newspaper are all suitable material. However, avoid planting large trees in fall. Leave the large trees to spring, and get a professional to do the moving. They have the proper equipment and expertise to help ensure a safe move.
This week I want to look ahead to next spring and discuss planting blueberries (Vaccinium sp.). Not many foods pack the antioxidant punch of this fruit, not to mention they taste great. Around the home they can be eaten fresh or made into jams, pies, muffins and many other recipes. Blueberries are an excellent choice for home gardens (as well as commercial pick your own farms) because they have fewer disease and insect problems compared to other small fruits, are very productive and long lived. These reasons also make it a great choice for organic production.
Many home gardeners shy away from growing blueberries because of their need for acidic soil but this can be solved by building raised beds filled with an acidic growing mix, amending the soil right in the garden bed, or even growing blueberries in containers. Blueberries also have a very high yield potential with as much as 10 pounds per mature plants. Spring is the best time to plant blueberries, so now is the time to look over nursery catalogs to choose varieties and order plants.
The most important factor in raising blueberries is the soil pH. I definitely recommend testing the soil where you are going to plant. Contact the Extension office for assistance in testing soils. Healthy, thriving blueberry plants require an acidic soil (pH 4.0 to 5.0) that is well-drained, loose, and high in organic matter. If the pH is over 7, it is best not to plant blueberries. If the pH is too high, the growth of the plant is slowed and the foliage discolors (called iron chlorosis). Eventually the plant dies.
If the pH is between 5.5-7.0, you can amend the soil with sphagnum peat moss. It will lower pH and add organic matter. You can also apply elemental sulfur, also known as soil sulfur. The material comes in pellets, granules, or powder and should be well mixed throughout the top four inches of soil at least three months before planting. If the pH is above 6.0, sulfur application should be made the year before planting. Contact the extension office for recommendations on how much sulfur to apply. Wear gloves when handling any form of elemental sulfur.
Site selection is key in planting this perennial fruit. Blueberry plants require full sun and like other fruit crops, do not like wet feet and must be established in a well-drained soil. The root system of this shrub is extremely fine and waterlogged soils will restrict growth. Raised beds can be used to provide a well-drained growing site for blueberries. Some growers may choose to tile their garden area to assure proper soil drainage.
I always say you have to have patience when growing small fruits and fruit trees. Blueberry plants grow slowly, which is part of why they’re so long-lived (some have been in production 20 or more years). Bare-rooted blueberry plants begin to produce fruit in the second or third season but do not become fully productive for about six to eight years. It is crucial for young blueberry plant to build a good root system and good sized canopy. Remove the flowers in the spring the first two years. Blueberry plants should not be allowed to bear fruit during the first two years after planting or until the plants reach a height of 2.5 feet. Allowing blueberries to produce fruit will reduce growth, resulting in a small, weak plant. Removal of flowers will allow more shoot and root growth and increase yields in the future.
There are four types of cultivated blueberries which include highbush, half-high, rabbiteye, and southern highbush. Highbush blueberries are recommended for West Virginia. Highbush blueberries do not require two different cultivars for cross pollination purposes but cross pollination will result in bigger berries and improved yields. I recommend planting at least two varieties for improved production and spreading the harvest season over a longer period. “Bluecrop” has been the standard variety for years, but many newer varieties are recommended including ‘Aurora’, ‘Chandler’ (very large berries),’Jersey’ (late season variety), ‘Patriot’ and ‘Spartan’. Varieties are usually labeled as early, mid or late season. Pollination by honey bees will also increase fruit set and yield.
Plant blueberry bushes about five to six feet apart in the row and allow at least 10 feet between rows. Plants in raised bed may be planted a little closer depending on the variety. There are specific varieties such as ‘Dwarf NorthSky’ and ‘Dwarf Tophat’ which can be grown in containers. A two year old plant is the preferred size of nursery stock to purchase. Mulching is a definite for blueberries due to their shallow root system. This not only suppresses weeds but reduces soil evaporation. Do not apply any fertilizer at planting, this will burn the roots. Ammonium sulfate is the fertilizer of choice due to its acidic nature to keep pH low.
The most serious problem of growing blueberries is birds eating ripening fruit. It will be necessary to build a structure with netting to protect blueberry plants during the harvest season. Blueberries store well, up to 14 days in the refrigerator.