Gardening with Gary

Gardening Advice from an Expert

Raspberries

Q. I bought some red and black raspberries Sat. (March 3). It is too early in Ohio to plant them, so what should I do with them until it is time to plant..etc watering, sun?

A. I believe that you are still under threat of frost and maybe snow. I know when I moved from Michigan eons ago, it was May 1st, and the prior week was very snowy!

Therefore, I do not want you to put them outside. If they feel warm, spring weather, then their buds will break and will be susceptible to frost damage! Try to keep them dormant until your frost date. A cool, dry, dark garage or basement would work.

Check them weekly as to their dryness. If they appear to need water, give them just a little and also mist them. Do not encourage growth until they are outside in their garden beds.

Cynthia writes~
Is there a trick to pruning raspberry bushes? I have many everbearing raspberry bushes that need a good pruning.

A. It is very important to understand the terms used to describe various parts of a raspberry plant before attempting to prune raspberries. Raspberry canes are of two types, primocanes and floricanes. Primocanes are first year canes while floricanes are second-year fruiting canes. Summer red raspberries should be pruned twice a year, first in the spring and immediately after harvest.

The spring pruning, in late March or early April, consists of removing all weak canes and cutting back tall canes (over 5 feet) to 4.5 to 5 feet. The second pruning consists of the removal of canes that produced fruits, right after harvest. Everbearing red raspberries such as "Heritage" raspberry can be pruned to produce fruit once a year or twice a year.

If you follow the pruning methods used for summer red raspberries, "Heritage" raspberry will produce fruit once in spring and once in fall. However, many home gardeners and commercial growers mow or cut all "Heritage" canes to the ground in early spring (March or April) for the sake of simplicity. "Heritage" raspberry pruned this way will produce only one crop starting in early August in southern Ohio, and mid-August in central Ohio. Black and purple raspberries are pruned three times a year: in the spring, summer, and after fruiting.

First pruning is done in spring when lateral branches are cut back to 8 to 10 inches in length in mid-March. Second pruning is called tipping or heading of new canes or primocanes. When grown without supports, summer tipping is done when black raspberry canes reach 24 inches in height and when purple types reach 30 inches. Tipping is done by removing the top 2 to 3 inches of new shoots as they develop. Third pruning involves the removal of canes that produced fruits, right after the harvest.

There are a couple very good diagrams of pruning at this website which furnished the information:

http://ohioline.osu.edu/hyg-fact/1000/1421.html

Q. The garden is mostly for my children and includes strawberries, a raspberry bush (It has grown quite nicely and has produced enough raspberries to keep my young children very happy), blackberries (just it's second year but doing quite nicely) and a blueberry bush. My raspberry bush has spread well and is about 6' wide and as tall. However, I noticed that the tips of several of the branches are wilted. It's just the last 10" and some have branches right beside it from the same main branch that are not wilted. Most of the bush is still quite nice. What's up and how do I fix it?

A. I imagine that you have a bacterial infestation as:

Phytophthora root rot, wet soil root rot, crown gall, Botrytis fruit rot, spur blight, Verticillium wilt, yellow rust, Anthracnose, and viral diseases, such as raspberry bush dwarf.

You need to take a sample wilted stem into your local Ag Cooperative Extension and have it analyzed. If you live near a small college or experiment station, they will help you. Check your local phone book under Government.

Otherwise, take the bagged sample to a reputable nursery or garden center. The product you will need to purchase and apply strictly according to the directions will be for sale and one or all of the above bacteria will be listed.

Do not fear, for this is a common disease and probably is soil-born. Make sure that your soil is well-drained and does not sit moist. In between rains, do not water unless the top 2" of the soil is dry.

Vicki writes~ I "Googled" pruning black raspberries and discovered your site. I understand the process as you are describing it. Our black raspberries came up randomly several years ago to our great delight - they are delicious! However, we have never pruned the bushes at all letting them do their thing naturally. I am concerned at this point about losing them. Is it too late to prune them as they were harvested in late June of this year? They are beginning to sprawl a bit and I would like to contain them if at all possible. We live in Indianapolis and have had a very strange summer here. As I type this it is down to 50F overnight. We are breaking records. Does this affect anything? Thank you for taking time to respond. I find your website very interesting and helpful.

Raspberries produce fruit on 2-year-old canes, which die after the crop has matured. The pruning of black and purple raspberries consists of: Tipping the new canes when they reach a height of 18-20", thus forming a branched cane that is capable of producing more fruit than an unbranched cane. Branched canes are also more able to support the crop off the ground than unbranched canes. As the buds break in the spring, the branches on the canes should be shortened to 8-12" [longer if the plant is supported by stakes or a wire trellis]. After the crop is harvested, the old fruiting canes should be removed at the soil line. The removal of the old canes as soon as the crop is harvested is a good disease control practice since it removes an important source of infection.

http://muextension.missouri.edu/explore/agguides/hort/g06000.htm

So, cut them back now and do not concern yourself with the weather. To avoid sprawling, unruly branches and reduced fruit next season, prune as soon as you can after all fruit has been harvested.

Derek writes~
My wife and I just started a raspberry garden. We got plants from friends. My question is how do we recognize a sucker?

A. A few years after planting raspberries, sprouts may come up several feet: into the lawn or other garden areas. To discourage brambles that sucker, place a barrier, such as galvanized sheet metal 12 inches into the soil. Otherwise, you must cultivate and remove the suckers as they spread. Factors which affect fruit production are: cane diameter and length, soil fertility and condition, amount of winter damage, and amount of sunlight and water. Pruning eliminates old canes, thins plantings to allow air circulation and sunlight penetration, and lessens competition for available nutrients and moisture. Raspberries are perennial plants with biennial growth and fruiting habits. Roots of these plants are cold-hardy and continue to produce aboveground growth from year to year. New canes, called Primocanes, are biennial in that they live two seasons. In the second year they are called Floricanes because they flower, bear fruit and then die. Each year new primocanes are produced, ensuring future berry production. New canes form at the base of the crown. These do not spread, nor are they suckers, which form a distance from the crowns:. Choose a site that is sunny and away from frost pockets. To combat the winter damage, choose a north slope or site on the North side of a windbreak or building. Winter shade will keep raspberries from breaking dormancy too early. Bramble root systems develop in the upper 10-20" of soil. Brambles should be grown in a sandy loam soil that contains organic matter, has good fertility and provides good drainage. Raspberries grow best in a soil pH of 5.8 to 6.5, but will grow and produce in many different soils. Use a soil test as a guide before applying lime or fertilizers.

For more information on fertilizing, mulching and pruning, check:

http://www.hcs.ohio-state.edu/mg/manual/fruit2.htm

Jen writes~
We found a raspberry bush growing on part of the land on which we are building our home. It is located right in the middle of the construction area. Is it possible for us to move the bush without damaging it, in order to plant it in another area of our property?

A. Cut back to short stumps about 6" long. Dig out and quickly move to the new site. Water well with water in which you have dissolved some Miracle-Gro. Transplanting is best carried out in the early spring just before new growth emerges. I would suggest pruning them after they go dormant in the fall or early next spring before new growth begins. The raspberry cane is a biennial one, in that it fruits on the second year's growth and dies down. So, the canes that bore this past summer should be cut out as they are dead and you do not want them to become vectors for transmitting diseases or insects to the new fruit bearing canes. Simply cut the old ones down to the ground and haul out. It is best to do this right after the canes are finished bearing or in either the fall or early the following spring. The best time to transplant is in the early spring when they are still dormant. Select only the healthiest crowns and reset them at the proper depth. Fertilize with 5-10-5 or something similar as the leaves open and again right after harvest.