Raspberries in Carbon County

THIS DISCUSSION ASSUMES A BASIC UNDERSTANDING OF THE PHYSIOLOGY AND BIOLOGY OF RASPBERRIES AND BLACKBERRIES. (For more basic and specific information on bramble production explore the links in the boxes to the right.)

Raspberries and blackberries are brambles. They can be grown successfully in Carbon County with proper care and environmental modification. For more information on the biology and physiology of brambles explore the links in the boxes to the right.

There are three things in the Carbon County environment that can cause problems for the erstwhile bramble grower—soil, spring winds, hot summers. Awareness and modification of these conditions will help berry growers in Carbon County be more successful.

There are many articles about general production practices for bramble fruits. Some of them are referenced in the box to the right. This website is to help deal with specific issues facing berry growers in Carbon County.

SOIL

Brambles prefer soils that have a lower pH than the soils of Carbon County. Modifications and amendments can be made that will help ease the negative effects of our soils on the productivity of brambles.

The chemistry of Carbon County soils is such that iron, and less frequently zinc, is not as readily available as brambles prefer; this results in a condition called iron chlorosis (or zinc chlorosis). Iron chlorosis can be easily recognized by the yellowing of the younger leaves while the veins remain a darker green color. In severe cases even the veins and older leaves may yellow. Successive years of iron chlorosis will result in weakened plants that will be more susceptible to diseases and insects.

Adding composted organic matter before establishing a berry planting will help with both pH and soil quality. Using fertilizer containing sulfur will also help the soil pH some. Finally, adding an iron amendment to the soil and applying a liquid chelated iron directly to the leaves of the plants will also help. Foliar application of chelates provides a very short term but rapid response. Chelates can also be applied to the soil and watered into the roots for a good response. Best results will be obtained by applying iron twice in the growing season, once in May and again in September.

Utah State University Extension Specialists recommend EDDHA-based chelates, such as Miller’s Ferriplus (Miller Chemical), Sequestrene 138 Fe (Becker Underwood) or similar product (generally designated with the “138” chemical identifier) at a rate of 1 to 2 pounds per acre banded along the row and then watered into the soil with at least one inch of irrigation water. Always follow the label directions of whatever product is being used. Keep in mind that the soil is a very large mass of very strong chemistry. In Carbon County soil amendments for brambles will likely be needed every year for the life of the plants.

There are many other general fertilization considerations for brambles, particularly nitrogen, phosphorus and potassium. Explore the articles in the box to the right for more care information.

SPRING WINDS

Carbon County is subject to cold, strong and prolonged winds in the spring. These winds can have a detrimental effect on the floricanes of both raspberries and blackberries, more particularly blackberries. To avoid wind problems either plant the berries in a protected spot, erect some sort of windbreak where you want to plant, or plant ever-bearing (primocane-fruiting) varieties.

HOT SUMMERS

Brambles produce very well in cooler summer temperatures. High summer temperatures during flowering and fruiting, such as experienced in late July and early August in Carbon County, can reduce overall yields and will certainly lower fruit quality. One common condition associated with high summer temperatures is the appearance of sun scald--bleached out (white) druplets on the sun-exposed side of the fruit. This condition can be circumvented by selecting varieties that produce a crop at times other than the high-temperature season of the summer. These varieties may be either very early summer-bearing varieties (this may be an exercise in futility) or ever-bearing (primocane) varieties. Study the characteristics of the varieties on the raspberry variety link in the box to the right.

Another management tool that will help with high, summer temperatures is to provide afternoon shade. This can be accomplished by planting on the east side of a building or structure, or erecting shade cloth—20% - 30% shade should be adequate. Proper irrigation management and a mulch that maintains cool root zone temperatures will also alleviate heat stress. Soil cooling mulches include clean wheat straw or white plastic.

These management considerations, in addition to regular cultural practices for brambles should help to make raspberries and blackberries productive over many years in Carbon County.