About Raspberries
Rosaceae
Relatives: Thimbleberry, Wineberry, Dewberry, Blackberry
Raspberry plants form several erect or sprawling stems each year. At the same time the 2-year-old canes die back. They usually have some thorns, but not nearly as many as blackberries (unless you have RRN Blackberries, which are thornless!). The roots of Raspberries are perennial thought the canes usually only live about two years. The first year of a new Raspberry's life is mostly spent growing vegetatively, while the second year they flower and produce fruits before the canes die back that second year. Raspberry can easily live for over 15 years.
Growing Raspberries and Blackberries
Growing Blackberries in North Carolina is fairly straight forward, but growing Raspberries requites a little explanation. While not really such a big deal, gardeners in our part of the world realize that Raspberries will suffer from the heat and humidity abundant in a North Carolina summer. And since we can't control the weather, we must look to controlling the plant. Specifically, in late January every year we cut back our Raspberries to about 3 to 4 inches in height. This cutting back forces them to spend much of their efforts the following spring and summer regrowing vegetation, with a reduced number of flowers available for pollination. Cooler nights in the late summer early fall will allow for more flowering, and the cooler weather brings larger and sweeter Raspberries.
Thornless Blackberries flower - and hence bear fruit - on last year's canes, so once they have fruited, they can and should be removed. We tend to remove the old / spent canes of Blackberries at the same time we are cutting back the Raspberries.
Selecting a Planting Site
To get the most out of your Blackberry and Raspberry plantings, choose your site carefully. Both berries prefer full sunlight and grow best in well-drained, sandy loam soils rich in organic matter. Avoid low areas that remain wet late into the spring, but select a site with access to a water supply. Irrigation is important for good plant growth during dry periods and can improve fruit size and yield. We recommend and employ a drip irrigation system in our pick your own berries here at Rabbit Ridge Nursery. Do not plant raspberries where tomatoes, potatoes, peppers, or eggplant have been grown within the past three or four years, because these crops carry a root rot called Verticillium that can also attack your berries. Destroy all wild raspberry and blackberry plants within a distance of 400 feet of your planting site if possible, to reduce the possibility that virus diseases might be spread to your planting.
Preparing the Soil
Getting the soil ready for berries may take up to two years, depending on its condition. Test the soil to determine its pH and fertility levels. Most berries prefer a soil pH of 5.6 to 6.2; acid soils may require applications of ground limestone to increase the pH. Soil testing information is available from your county Cooperative Extension office, and is free if you choose off planing times. You can improve the level of organic matter in the soil and discourage perennial weeds by sowing a cover crop such as buckwheat, rye, millet, or oats, and plowing it into the soil before it goes to seed. There should be time enough for two sowings in a single season. Applications of barnyard manure or compost and repeated tilling for a full season can be substituted for cover cropping. Be aware that animal manures may contain weed seeds that can become a problem in your planting later. In the spring of the planting year, spread 25 pounds of 10-10-10 garden fertilizer per 1,000 square feet of planting site. Organic fertilizer sources such as compost, manures, sul-po-mag, and rock phosphate may be used in place of synthetic fertilizers. Apply enough of these materials to deliver two pounds each of nitrogen, phosphorus (P2O5) and potassium (K2O) per 1,000 square feet. Cultivate the soil several days before planting to incorporate the fertilizer and break up any clumps or clods.
The Raspberry and Blackberry Plant
The crowns and roots of both berry plants are perennial, but individual canes live two years. Each spring, the plants produce canes (suckers) from buds on the crown and on underground lateral stems. These canes grow vegetatively during the first season, overwinter, and produce fruit during the summer of the second year, while new canes emerge to provide a crop for the following year. Second-year canes die shortly after fruiting. Everbearing raspberries bear a crop on the tips of first-year canes in the fall, followed by a typical summer crop on the lower portion of the canes the second year.
It’s easy to tell first-year canes from second-year canes. First-year canes have green stems, while second-year canes have a thin, brown bark covering them. We remove all the brown Blackberry canes in January and February, but you may remove them once they have finished fruiting.
Order your berry plants from a reputable nursery or garden dealer. Specify disease-free, virus-indexed stock. Most Raspberries and Blackberry plants are sold as dormant, one-year-old canes, but we also sell potted Black and Raspberry plants that are not dormant.
Suggested Varieties
Red Raspberries
Nova, Dorman Red, Heritage Red, Amity and Fall Gold
Blackberries
Apache, Logan, Navajo, Ouachita, Triple Crown, and Tayberry
Planting and Management Systems
Plant raspberries early in the spring after the danger of severe frost is past (late April to mid-May). Do not allow plant roots to dry out before or during planting. Plants should be set at the same depth or slightly deeper than they were in the nursery. Firm the soil around the roots and water the plants. If one-year-old canes are used, cut them back to a height of four to six inches above the ground.
Red raspberry plants are typically grown in a hedgerow. Crowns should be planted about 2 feet apart in rows that are 8 to 12 feet apart. Choose the wider spacing if you’ll be using large equipment, such as tractors, in the planting. The plants will soon send up suckers from the roots and crowns to form a hedge, which should be maintained at 12 to 18 inches wide at the base.
All raspberries should be grown with some sort of a trellis. This will improve fruit quality, make harvesting easier, and reduce disease problems. Trellises also make pruning simpler by encouraging new cane growth in the middle of the row, rather than just along the outside edges.
For the T trellis, sturdy posts should be set in the row with 3½-foot-long cross arms affixed at a height of 3½ to 4½ feet. The posts should be set at least two feet deep in the ground and anchored at each end of the row. Secure heavy-gauge wire along the length of the row on each side of the cross arms.
DESCRIPTION
LEAVES: Compound, 3 to 5 leaflets, with the middle leaf being the largest. The leaves are coarse to the touch, somewhat rough, and the margins are serrated. The leaves have a pleasant smell when crushed in the hand. The leaves on the 2-year old canes (fruiting canes) seem to become darker and a little thicker before dying off; this will help you determine the first and second year canes from each other.
FLOWER: Quite small, white to pale pink in color, and are born terminally in small clusters. The receptacle consists of 60-80 embryos, which can and often do develop into drupelets. The flowers give off a lot of nectar, which is of course appealing to insects and bees. Although Raspberries are indeed self-fertile, you will almost always see them planted in groupings.
FRUIT: Numerous drupelets, or really just flesh-covered seeds, clustered around a receptacle, which is left behind when the fruit is picked. This leaves the fruit with a hollow center Fruits really only take about 30 to 35 days to form after pollination. One of the time consuming aspects to growing Raspberries it the harvesting itself, as they tend to ripen over a period of days in the fruiting season. You may have to harvest as often as every two to three days. The fruits themselves are easily crushed or damaged, and for that reason, it is best to pick them in shallow baskets. Once harvested, they only remain really nice for three or four days under refrigeration. But despite the hassles, if you have never eaten fresh Raspberries from your own vines, you have no idea how much better they are than the Grocery Store Varieties you buy in the little plastic domes.
CULTIVATION
LOCATION: Raspberries like sunny areas in cooler climates, but actually enjoy part shade in the heat of our North Carolina summers. They will fruit in sun or shade but are not particularly salt or wind tolerant. They are very frost tolerant and can withstand long, cold periods. Red Raspberries need a little winter chill in the 800 hour range. Plants grow best in a slightly acidic soil that have good potassium levels. We have found that our Raspberry plants grow much better with the spring time application of a organic ground cover, which also keeps the roots cooler in our hot summers but tends to keep the grass and weeds at bay. They are not particularly drought tolerant, and will need supplemental watering when the weather is dry and the fruit is developing. DO NOT over fertilize with nitrogen as this results in too much leaf growth at the expense of fruiting. Once established, Raspberry plants take on an over lapping cycle of maintenance with respect to pruning, as the two year old canes are pruned out as they finish fruiting and you work with the newer, one year old canes. All damaged canes should be removed. Expect about the same level of pests and diseases as you have with Blackberries, but you must also count on the competition of both the two and four legged creatures in your area.
CULTIVARS
As you can see from above, there are many, many cultivars of Raspberry on the market today, varying in size, taste, color, shape, and on and on. The problem with ALL of them is that the fruit is so soft and tender, it has virtually no storage potential and needs to be consumed / used within a day or two of harvest. (Raspberries are probably the most often thrown out commodity in an entire Grocery Store for just this very reason).....but that won't be as much of a problem if you grow your own.
Spring / Summer-bearing cultivars produce canes that are biennial in habit (live two years), growing one year and producing fruit the next year.
Everbearing (fall-bearing) cultivars produce canes that bear fruit on the top portion of the current season's growth in late summer to fall (generally in late August to early October). If you leave these canes for the next year, they will bear fruit on the portions that did not fruit the previous fall. Therefore, with Everbearing Raspberries, you can produce fruit in both June-July on the base of last year's canes and once again late summer-early fall on the top of the current season's canes. Pretty cool, but as mentioned above, the heat and humidity of North Carolina tends to make Raspberries small and less sweet than those grown in the later summer and on into fall.
Both our Raspberry Cultivars are Everbearing types.
NOTE: If you prune for as above for a two crop harvest, the spring crop will be small. If you only want one large harvest, then in March or early April, simply prune all the canes back to ground level and you will have a very large fall crop. This is how I manage my own Raspberries, preferring to harvest a large crop of berries on into November.
We currently offer the following Raspberry cultivars for sale here at Rabbit Ridge Nursery, which are proven to do very well in our hot and humid North Carolina summers. All our Raspberries are at least three years old at time of sale, are of bearing age, and are on their own roots.
Click on the Raspberry below to learn more about it.
PRUNING
This information is from the NCSU website....a very trusted source of information for all gardeners in NC.
"The canes of raspberries are biennial -- they grow for one year and then produce flowers and fruits during the early summer of the second year. The second year canes die shortly after harvest, and should be pruned out as soon as harvest is over.
All raspberries produce new canes, called primocanes, to replace those that die. Red raspberries produce primocanes from crown buds and from buds along roots (root suckers). The root suckers come up at random and result in a thick bramble patch if not controlled."
Expect your Raspberry plants to double in size in a few years.
TWO CROP option: For two small crops, one in July and one in September, remove the weakest, thinnest canes with dead flowering or fruiting bracts.
ONE CROP option: For one large late summer crop, remove all canes, and the crop will come entirely from the new summer’s growth and produce berries in September through October.