By Donnetta Wilhelm
There are many small fruits (known as berries) that are well-suited to Colorado. (The gardening term “small fruit” refers not to fruit size but to fruit borne on smaller perennial plants rather than trees.)
Favorites that can grow here include strawberries, raspberries, blackberries, currants, grapes and gooseberries. Colorado also can produce “alternative” small fruits, including elderberries, chokeberries, honeyberries, goji berries, Nanking cherries and huckleberries. With specific growing conditions and a gardener with an adventurous spirit, blueberries are also achievable.
Those who add fruit to their gardens are sure to enjoy a flavorful harvest.
Strawberries are rich in antioxidants, fiber, and vitamin C — even more than oranges. They contain anthocyanins, are low in calories, have a low glycemic index, and are easy to grow.
Strawberries need at least 8 hours of sun and grow best in sandy loam or amended soil. Irrigate about 1 inch per week, mulch to retain moisture, and fertilize in summer and fall. Keep the soil moist until the first frost, then withhold water to harden off the plants. Mulch well as cold weather arrives, and water occasionally during dry winters to prevent winter kill.
Strawberries fall into three classifications:
- June-bearing plants are best planted in rows, spaced 2 feet apart with rows 4 feet apart for a path. The plants produce runners that fill the space. June-bearing types produce one large crop in late June to early July. Good varieties for the Front Range include Guardian, Kent, Honeoye, Rechief, Delite, and Bloomiden.
2. Everbearing varieties for the Front Range include Ogallala, Fort Laramie and Ozark Beauty. Plant these using the hill system: place each plant 1 foot apart in raised mounds (hills), and leave a path between rows for access. Remove runners consistently to keep the plant focused on fruiting. Everbearing strawberries yield two crops each season: one in June and another in late summer.
3. Day-neutral is the third classification, flowering and fruiting regularly over the summer. Recommended varieties include Tribute, Tristar and Fern. Use the hill system, plant in single rows spaced about 1 foot apart, and remove runners to maintain productivity.
Raspberries are a nutritionally powerful food. They are rich in fiber, vitamin C and manganese, but low in calories, fat and sugar. Raspberries are also rich in polyphenols, plant compounds known to help reduce chronic inflammation.
Raspberries are planted in spring, spaced 2-3 feet apart in rows that are 5 feet apart. Suckers fill the row to form a hedge of canes. Raspberries need 6 hours of sun and grow best with protection from intense afternoon sun and hot winds. They thrive in most soil types but need organic matter and good drainage. Provide 1 to 3 inches of water per week and fertilize to boost soil fertility. After autumn frost, reduce watering to harden off the plants, and water occasionally during dry winters.
Red raspberries are classified as summer-bearing or fall-bearing. Recommended Front Range varieties for summer bearing are Latham, Boyne, Newburgh, Canby and Titan. Good fall-bearing varieties include Redwing, August Red, Heritage, Fall Red and Fall Gold (a yellow variety).
Summer-bearing varieties produce canes in the first season and bear fruit on short lateral branches the following summer. These raspberries generally require a trellis support system to keep them standing upright. After fruiting, cut summer-bearing canes off at the ground. For winter protection, lay the canes in a trench and cover with soil.
Fall-bearing varieties also produce canes, but these fruit in August and September of the first season. Fall-bearing types usually do not need trellising. After the fall harvest, cut canes to ground level. Winter protection is not needed.
Blackberries are packed with vitamin C, vitamin K, manganese, fiber and the antioxidant anthocyanin. Many Colorado gardeners grow blackberries successfully, but these plants need specific care to handle the cold, dry, windy climate, and trellising is required.
Blackberries are planted in the spring and located in a protected location. Full sun is best, but they can tolerate partial shade. Although blackberries tolerate heavy soil better than raspberries, amend the soil with 5% organic matter and ensure good drainage. Space plants 2 to 6 feet apart, depending on the cultivar, and keep them mulched year-round, especially during summer heat. Provide 2 inches of water per week.
Blackberry types include trailing, erect and semi-erect. CSU strongly advises planting erect or semi-erect cultivars, as trailing cultivars are not hardy in Colorado.
Erect blackberries are self-supporting with shorter, stiffer, arching canes, but can be better managed with T-trellising. They require management to prevent invasive suckering. Varieties such as Prime-Ark Jan, Prime-Ark Jim and Ponca are recommended.
Semi-erect blackberries produce higher yields than other types. They are thornless and need a Double-T trellis for cane training. Good cultivars are Triple Crown, Chester Thornless and Natchez Thornless.
Unfortunately, Colorado gardeners cannot grow blueberries using traditional in-ground methods. Blueberries require acidic soil with a pH of 4.0 to 5.5, but most Colorado soils are alkaline, with a pH of 7.0 to 8.3. Persistent and resourceful gardeners have grown blueberries using three essential components: selecting planting materials with a pH of 5.5 or below; keeping the root zone consistently moist year-round; and shielding the bushes from drying winter winds.
Sphagnum peat moss (pH of 3.5 to 5.5), is available at local garden centers and can be used as the main planting medium in several ways:
- The bale planting method involves digging a hole for the plastic-wrapped sphagnum peat moss bale. Punch large holes in the bottom of the plastic and place the bale in the hole. Cut an “X” in the plastic top and plant a bare-root blueberry in the peat moss. Re-close the “X” with tape, leaving a 3-inch hole in the middle for the trunk. Run drip irrigation by feeding the line through so it sits between the peat bale and the plastic.
2. The soil replacement method removes existing soil from a planting area to a depth of 3 feet. Replace it with 1/3 good commercial topsoil, 1/3 sphagnum peat moss, and 1/3 shredded pine bark. Submit a sample of the mix to a soil testing lab for pH testing before planting.
3. The raised bed method uses a bed at least 3-4 feet wide and as long as desired. Depth should also reach 3 feet to prevent blueberry roots from entering native alkaline soil. Use the same specialized soil mix as in the soil replacement method. Another option is a converted water trough found at farm stores and drainage holes drilled in the bottom. For these methods, blueberry varieties such as Blueray, Elliott, Patriot, Northblue, Northsky and Burgundy are reliable choices.
Smaller-sized and dwarf varieties are good for the container planting method. Use half-barrel planters or a large 24-inch plastic pot with additional drainage holes. Fill the container with the soil mix mentioned above. Containers can be sunk into the ground or used above ground, making sure to winterize appropriately. Recommended container varieties include Peach Sorbet, Blueberry Glaze, Jelly Bean, Midnight Cascade and Sapphire Cascade.
Whatever the method, keep soil consistently moist during the growing season. Check the top inch of soil for dryness before watering. Mulch around the base to conserve moisture and keep the roots cool. Fertilize with a balanced fertilizer for acid-loving plants in early May and July. Check soil acidity annually and amend as needed. Wrap dormant plants in burlap or sheets to protect from winter winds. Water during dry winters as needed.
With one in three U.S. households growing food at home or in community gardens, even the most common fruits are often overlooked as a garden food source. Adding fruit to the home garden is well worth the effort.
Fore more information, consult the , which has helpful resources that can help a beginning fruit grower understand trellising, pests and disease control, fertilization, pruning and harvesting.
Donnetta Wilhelm is a Colorado master gardener.
