Tag: trellising

Growing Grapes in Colorado Gardens: A Comprehensive Guide

Growing grapes in Colorado can be a rewarding experience, whether you’re aiming for fresh table grapes, juice, or even homemade wine. This guide will walk you through the essential steps for successful grape cultivation, from choosing the right cultivars to planting, trellising, pruning, and general care.

Types and Cultivars

Types of Grapes:

  • Table Grapes: Ideal for fresh eating, with popular seedless varieties like Himrod, Interlaken, Canadice, St. Theresa, and Reliance.
  • Juice and Jelly Grapes: Popular cultivars include Concord, Valiant, Niagara, and St. Croix.
  • Wine Grapes
  • Raisin Grapes

Cultivars:

  • American Cultivars (Vitis labrusca): Known for their strong “foxy” (musty) flavor and aroma, these are used for juice, fresh eating, and some wines.
  • European Cultivars (Vitis vinifera): With tight clusters and thin skins, these grapes are used for wines and require more heat units for maturity, making them less suitable for Colorado.
  • French-American Hybrids: Popular for wine, with characteristics that vary depending on parentage.

Planting Grapes

Grapes need full sun and protection from wind. Space plants 6 to 8 feet apart, in rows 6 to 10 feet apart, depending on your trellising system. Strong trellising systems are necessary to support the heavy vines and fruit. Use treated posts and 12-gauge or heavier wire.

Trellising and Pruning

Grapes fruit on one-year-old wood, making pruning a balance between fruit production and renewing wood. Proper pruning is essential for high yields and large clusters of grapes. Unpruned or under-pruned grapes will produce many small clusters of tiny grapes, while over-pruning reduces yield.

Single Curtain System:

  1. Pruning at Planting: Cut back to two to three buds to encourage the growth of a strong primary trunk.
    • Image provided by CSU extension
  2. Second Spring Pruning: Select one cane to become the trunk and remove others, leaving one or two renewal spurs.
    • Image provided by CSU extension
  3. Third Spring Pruning: Select two one-year-old canes to become fruiting canes and cordon arms along the trellis. Prune two other canes back to two buds each to serve as renewal spurs.
    • Image provided by CSU extension
  4. Fourth Spring and Beyond: Continue selecting new fruiting canes and renewal spurs each spring, maintaining the balance between fruit production and new wood growth.
    • Image provided by CSU extension

General Care of Grapes

  • Mulching: Use a four-foot-wide weed-free bark/wood chip mulch strip under the trellis to help retain moisture and reduce weed competition.
  • Watering: Avoid over-watering, as it can lead to iron chlorosis.
  • Fertilization: Go light on fertilization. Apply one-fourth cup of 21-0-0 (or equivalent) per established plant, broadcast under the trellis, and water in.
  • Harvest: Flavor is the best indicator for home gardeners to determine harvest time.

Common Grape Pests

Fruit:

  • Birds: Bird netting may be necessary to protect the fruit.
  • Botrytis Bunch Rot: Often a problem with heavy canopies due to inadequate pruning and poor air circulation.
  • Spotted Wing Drosophila Flies: These can affect ripe grapes.

Plants:

  • Powdery Mildew: Refer to CSU Extension Fact Sheet #2.902 for management.
  • Iron Chlorosis: Typically a symptom of over-watering. Refer to CSU Extension CMG GardenNotes #223 for more information.
  • Root Rots: Poor soil drainage can lead to root rot issues.
  • Weeds and Diseases: Grapes do not tolerate competition well, so adequate control is necessary.

By following these guidelines, you can enjoy a bountiful grape harvest in your Colorado garden. Happy gardening!

For more detailed information, call or visit Echter’s Garden Center or contact your local CSU Extension office.

Growing and Pruning Raspberries in Colorado: A Comprehensive Guide

Raspberries are a delightful addition to any home garden, providing delicious fruit and vibrant foliage. In Colorado, only selected varieties of red and yellow raspberries are recommended due to the state’s unique climate. This guide covers everything from choosing the right varieties to effective pruning techniques, ensuring you enjoy a bountiful raspberry harvest.

Suitable Raspberry Varieties for Colorado

Red and Yellow Raspberries:

  • Best for general cultivation in Colorado.
  • Recommended varieties include summer-bearing types like ‘Nova’ and ‘Boyne,’ and fall-bearing types suitable for the Front Range and Western Slope.

Black Raspberries:

  • Hardy varieties such as Niwot and Pequot can thrive in some Colorado areas.

Other Varieties:

  • Blackberries, purple raspberries, boysenberries, loganberries, and dewberries require special winter protection and are less recommended.

Types of Raspberries

Summer-Bearing (Floricane):

  • Produce flowers and fruit on second-year canes.
  • Fruit once per season.

Fall-Bearing (Primocane or Everbearing):

  • Produce flowers and fruit on first-year canes.
  • Can provide two harvests: one in fall and a lighter one in summer on the lower parts of the canes.
Chart Provided by CSU Extension

Soil Preparation and Planting

Soil Requirements:

  • Well-drained garden soil rich in organic matter.
  • Conduct a soil test to determine nutrient needs, especially nitrogen, zinc, iron, and manganese.

Planting:

  • Plant red and yellow raspberries as rooted suckers in spring.
  • Space plants 2-3 feet apart with rows 5-10 feet apart.
  • Cut tops to 4-6 inches above ground after planting.

Pruning Techniques

Red Raspberries:

  • Can be trained to a single stake or supported by horizontal wires 18” apart.
  • Freestanding canes should be headed back below 4.5 feet to prevent bending.

Black and Purple Raspberries:

  • Less vigorous and pruned heavily.
  • Often left freestanding.

General Pruning Tips:

  • Remove spent floricanes after fruiting to prevent disease.
  • In spring, remove dead, weak, and small canes.
  • For fall-bearing varieties, either mow all canes to ground level after harvest or remove the fruited cane parts, leaving the lower portions for summer fruit.

Trellising and Support

  • Trellising is advisable to keep canes erect and simplify harvesting.
  • Use wires 3 feet above ground to confine canes to the hedge row.
  • Larger fruit can be achieved by tipping canes at a convenient height.

Watering and Fertilization

Watering:

  • Maintain moderate moisture in the root zone.
  • Increase watering during flowering and fruiting periods.
  • Withhold water after the first frost to harden off plants.

Fertilization:

  • Apply nitrogen fertilizer as needed based on soil tests and cane growth.
  • Fall-bearing raspberries require more nitrogen than summer-bearing varieties.

Winter Protection

For Summer-Bearing Varieties:

  • Lay canes down and cover with soil or mulch after November 1.
  • Lift canes in early April and return the soil to the furrow.

For Fall-Bearing Varieties:

  • Mow canes after harvest to avoid winter damage.
  • If a summer crop is desired, protect canes similarly to summer-bearing types.

Yield and Longevity

  • Expect 15-20 pounds of fruit per year from a 25-foot hedge row by the third year.
  • Productivity may decline after 8-10 years, necessitating relocation of the raspberry bed.

Disease and Pest Management

Common Pests:

  • Spider mites, which can be managed by maintaining healthy, well-watered plants.
  • Raspberry cane borers, identified by wilting cane tips, can be controlled by removing affected canes.
  • Spotted wing drosophila, managed through refrigeration, cleanup of dropped fruit, and trapping.

Preventative Measures:

  • Purchase disease-free stock from reputable sources.
  • Regularly thin canes to improve light and air circulation.

By following these guidelines, you can successfully grow and enjoy raspberries in your Colorado garden. For more detailed information and expert advice, contact Echter’s Garden Center or refer to resources from Colorado State University Extension. Happy gardening!