Rubus - Blackberry, Blackcap, Boulder Raspberry, Boysenberry, Brambleberry, Cloudberry, Dewberry, Ghost Brambles, Loganberry, Raspberry, Salmonberry, Thimbleberry, Whitewashed Brambles, Wineberry
DESCRIPTION: Rubus belongs to the Rose family. This group consists of erect, arching or trailing, deciduous and evergreen shrubs found wild in Europe, North America and Asia. Some are very ornamental, while most are grown for their edible fruits. Of the varieties, the most popular are R. idaeus vulgatus, commonly known as the European Raspberry, R. idaeus var. strigosus, the American Raspberry, R. occidentalis, the Black Raspberry, Blackcap, or Thimbleberry, and the Raspberry's cousin, the Blackberry. Varieties of the Blackberry that also have deliciously edible fruits are commonly known as the Dewberry, Boysenberry and Loganberry.
Raspberry & Blackberry: The Blackberry is a close relative to the Raspberry, but the two can easily be distinguished. When picked, the stem and receptacles of the Raspberry stay on the plant and the fruit is hollow. However, the stems of a Blackberry stay on the berry and the fruits are not hollow. Blackberries aren't as popular as Raspberries, but are just as delicious. Blackberries can yield more than Raspberries and there are cultivars that still bear even after the summer Raspberries are gone. Blackberries aren't as popular because the selection of cultivars isn't as wide as with Raspberries and as of yet there aren't any cultivars that can consistently produce in regions where winter temperatures fall below -20º F. However, Blackberries will produce as far south as Ft. Myers, Florida. Blackberry canes have more thorns and grow more vigorously, therefore need more attention to keep them under control. Lastly, the berries are ordinarily softer than those of the Raspberry and don't keep as well.
Raspberries: Raspberries are found from the frigid arctic regions to the warm semi-tropics. In the arctic, mature plants are small, with pretty little flowers and fragrant fruit. In warm climates, Raspberries may form thickets of long, climbing vines. In between are found the berries we use in jams and on cereals, the European and American varieties of the red Raspberry and the Black Raspberry. American Raspberries are round, while the European varieties are long and conical. Raspberries can come in black, shades of purple, and in various shades of yellow, from off-white to gold, to a slightly orange tinge. There is a wide variation in flavor, firmness, seediness and in drupelet cohesion (a term that describes the berry's resistance to falling apart). Raspberries are an aggregate fruit, which means they are composed of individual drupelets, held together by almost invisible hairs. Each drupelet usually has a single seed, though a few have two. Raspberry canes may be armed with formidable spines and make great security hedges, while others may be nearly spineless; excellent for easy harvesting and young children. Raspberries can be classified in several ways. Raspberries have perennial roots and biennial foliage and fruit-bearing canes, which means the branches live only two growing seasons before dying. Raspberries bear either in the fall or summer. The easiest to grow are the fall-bearers, called primocanes; these bear the fruits on the canes developed during the current growing season. Once snow is gone in late winter or early spring, prune off the last season's canes just above ground level. The new canes that grow that summer will produce the crop in the fall, as early as mid-July to late November, depending on the variety and your location. Summer-bearers are called floricanes. These bear fruits on canes that have overwintered from the previous year. These aren't as easy to grow because the canes must be able to survive the winter unharmed to produce a good crop and while the overwintered canes are producing, new canes are forming and competing for nutrients. Also, after bearing their crop, the second-year canes die and need to be removed. Three things will help you choose which Raspberry variety will suit your needs and climate. First, decide how you plan to use your berries. If your going to eat them fresh, choose cultivars with intense flavor and eye appeal. If you make preserves, texture and color after processing are important. Yellow berries can be unattractive when processed. Purple berries are great for processing and pastries. They have high yields and are easily harvested. Their fragrance, flavor and rich red coloring are superb. Secondly, decide which cultivar will suit your climate. For example, northern gardeners should choose summer-bearing cultivars that are winter hardy. In the south, summer-bearing cultivars should be chosen according to the number of chill hours they require and the amount of heat they'll withstand. Lastly, decide when you want to harvest your berries. Summer-bearing varieties will produce for about three weeks. For a longer harvest season, plant two summer-bearers, one early and one late, and two in the fall, one early and one late. Gardeners in cold zones can plant two summer-bearers but only an early fall-bearing type.
Blackberries: Blackberries are less cold hardy than Raspberries, but they can withstand more heat. There are only summer-bearing Blackberries, which ripen later in the summer than Raspberries. Blackberries, like summer-bearing Raspberries, produce fruit on the previous season's canes, which die after bearing fruit. Blackberries are classified as either erect or semi-erect Eastern types or trailing Western types. These classes may be either thorny or thornless. Ordinarily, thorny Blackberries are sweeter. Thorny Blackberries are hardier than thornless Blackberries because they can survive temperatures down to -5º F. Thornless Blackberries are hardy down to about 0º F. They are vigorous, erect or semi-erect growers that need much wider spacing than black or purple Raspberries. Western Trailing Blackberries have fragrant, flavorful, soft fruit that doesn't keep well. They are excellent for eating or processing immediately. Western Trailing Blackberries also bear in the summer on the second year's growth, though they produce less fruit than the erect or semi-erect types. These Blackberries should be grown on strong trellises. Western Trailing Blackberries are less hardy than the Eastern Blackberries; their flowerbuds will die at temperatures below 15º F. These varieties will grow best along the Pacific coast and in mild valleys inland from the sea where the soil hardly freezes.Boysenberries, Dewberries and Logan berries are all trailing types of Blackberries
POTTING: Raspberries and Blackberries have similar cultivation requirements. Any differences between the types of Raspberries and between the two will be mentioned below. Brambleberries can be grown in good, moisture retentive, garden soil that drains well. The roots will die in waterlogged soil. It would be beneficial to add organic materials to your soil, such as compost and well-rotted manure. They should have a slightly acidic soil with a pH of 6.0 to 6.7. If your soil is slightly alkaline, apply iron and manganese. Brambles grow best in full sun, although if your climate is hot it is better to site them in a location that will receive partial shade during the hottest parts of the day. They should be sheltered from hot summer and cold winter winds. They should receive adequate ventilation, especially in humid atmospheres, to reduce chances of fungal diseases. Brambles are sold as dormant, bare-rooted plants that can be planted in the spring in cold-winter regions or in the spring or fall in regions with mild winters. In sandy soil, cover with about two inches of soil; in heavy soil, cover the roots with about an inch. Cut down the canes right after planting or else they will bear fruit in the summer, thus taking energy from the newly planted roots. You must make sure your plants have enough water. If your soil is light and sandy, provide an inch of water every four or five days. If your soil is rich in organic matter, an inch every week or so should be sufficient. It is better to water at the roots instead of spraying all over the branches, as this could cause fungus. It would be beneficial to mulch the ground underneath the plants with well-matured compost. In the spring, it should be drawn away from around the plants until the ground warms and new shoots arise. Once the soil temperatures have risen, re-apply mulch to keep the ground cool, moist, and weed free. If you have good soil, a moderate application of a balanced fertilizer each year is enough nutrients for your plants to flourish. Avoid feeding high-nitrogen fertilizers, especially after the plants have blossomed. Potassium is much more important in the development of high quality fruit.
Raspberries - Fall-bearers: This type is easy to grow. They need adequate water and compost or fertilizer. Their growth will need to be monitored, as they tend to spread. You can control their growth by placing plastic or wooden barriers down about ten or twelve inches into the ground, since Fall-bearers multiply from the base of the mother plants and from root suckers. This type spreads 12 to 18 inches a year in all directions. If you want a solid row in a year, space the new plants a foot apart. If you want a solid row in two years, space them two feet apart. You need to have some kind of trellis because the weight of the fruit will bend the canes down. When the snow is gone at the end of the winter, cut or mow the canes to the ground. Red and yellow Summer-bearers: These types are treated like Fall-bearers. The main difference is that you need to remove the second-year canes after they've produced a crop. As soon as you've finished harvesting, cut off all the dead canes. Prune when they are dry to minimize the spreading of fungus. You will increase the air circulation and light penetration by thinning out the canes like this. While you're removing the old canes, discard any new canes that are thin, diseased, or growing in unwanted directions. In late winter or early spring, thin all summer-bearing red and yellow cultivars. Leave only the heaviest, strongest, and healthiest canes. There should only be two to four canes per square foot of row. This will help in the development of large berries. You can also prune off the top six inches of the canes at this time. Black & purple Summer-bearers: Most of these types don't spread like the yellow and red Raspberries. They should be planted about 3 feet apart. When new canes have a good start on growth, first-year canes should be thinned in late spring or early summer to about five or six of the heaviest new canes to a clump. When the new canes are about waist high, prune off the top 3 to 6 inches. This will cause them to branch out; the fruit of the following year will grow from these new branches. If you don't prune back the new canes, they will grow extremely long. If, when the next year rolls around, the lateral branches are too high to harvest from, adjust the height at which you prune them until they are at a reasonable height for you. Second-year canes, which are the ones that bear the current season's crop, need to be trimmed in late winter or early spring before the buds swell. Only leave 8 to 10 of the largest branches and trim these back to no more than 8 to 12 inches in length. Immediately after harvest, cut out the dead, second-year canes. Black Raspberries are more susceptible to fungus, therefore make sure to apply lime sulfur in early spring.
Blackberries - Thorny: Thorny Blackberries should be treated like black or purple Raspberries. When the first-year canes are about 36 to 48 inches high, cut off the top few inches. This forces branching and stiffens the canes. Cut the new lateral branches down to about a foot long in late winter and completely remove thin ones. Thornless: Thornless Blackberries should be planted 4 to 6 feet apart. Shorten first-year laterals to 12 to 18 inches in length and completely remove thin ones. In late winter, thin canes to four to six canes per crown. Western Trailing: Plant this type 6 to 8 feet apart and train them to a strong trellis. Let the first-year laterals grow, cutting out only the diseased and weak canes.
Supporting Brambles: Although you can allow Red Raspberry hybrids to grow as shrubs, trellising your plants makes harvest easier and allows you to control their growth much better. Keep these important factors in mind when constructing a support system: there should be great air circulation to keep foliage and branches dry, which prevents attack from fungus; it should allow as much sunlight as possible to reach the foliage and branches and keep the canes fairly erect so that you can be close to the row to harvest the fruit at a comfortable height. Single-fence trellises take up less room than double-fenced trellises, but they hold less canes. A single-fenced trellis is made by inserting 4x4 posts 11/2 to 3 feet into the soil and tying galvanized wires at 21/2 feet, 4 feet and 51/2 feet from the ground between the posts (which are supported with guy wires). The canes and long laterals are tied to the wires with twine or twist ties. Canes can also be looped horizontally around the wires. A double-fence trellis is constructed by inserting into the ground 4x4 posts that have 21/2 to 3 foot long, 2x4 wood crosspieces attached at 21/2 feet above the soil's surface and 4 to 5 feet above the soil's surface. Wires are then attached to each end of the crosspieces and connected from crosspiece to crosspiece down the row. Cross wires may also be placed every 2 feet along the length of the wires for additional support. You can tie canes to the wires with twist ties with half to one side and half to the other, leaving the center open for ventilation and light and new canes to penetrate. Canes can be tied with twist ties to the wires and/or looped around them; be sure to keep up with the growth as it is much easier to tie canes before new foliage makes it difficult to do.
Harvest: Summer-bearers can be ready to harvest by May or as late as July. Fall-bearers can be harvested until frost. If your frost comes early, cover the plants for a night or two with plastic or some other sheeting material. Once the Raspberries are ripe, they must be picked or else they will quickly turn bad. They should be observed closely as they ripen. They should be picked as early in the day as possible, but not until the dew has dried unless you plan to use them right away. Rinse them just before use. The berries should be stored as close to freezing as possible. It ordinarily takes 40 to 45 days from the time they bloom until they ripen.
Pests and Diseases: Raspberries (especially Black ones) are vulnerable to fungal, bacterial, and viral diseases. There isn't much you can do about viral infections, except purchasing virus-clean stock. Fungal and bacterial disease can be hard to diagnose correctly, but if you take proper care of you soil by adding compost and natural amendments and providing adequate ventilation and water, you should escape many problems. A good preventative is to spray the canes (once the leaves have emerged 1/4 to 1/2 inch) with lime sulfur. This natural product helps prevent three major fungal diseases. Timing is extremely important; if done too early, the spray won't be effective. If you do it too late there won't be as much a problem; it may just burn back the larger leaves a bit.
PROPAGATION: Purchase edible varieties according to your region. Ornamental varieties may be increased by sowing seeds as well as by cuttings or layering the branches.
Temperature noted by each variety is coldest temp. it can survive.
VARIETIES: Raspberries: Floricane/Summer-bearing - Algonquin -25ºF; Canby -20ºF; Bababerry -10ºF; Chilliwack -15ºF; Killarney -35ºF; Latham -40ºF; Newburgh -20ºF; Nova -30ºF; Titan -25ºF; Tulameen -5ºF. Black Raspberries: Floricane/Summer-bearing - Black Hawk -25ºF; Bristol -20ºF; Cumberland -20ºF; Haut -20ºF; Jewel -25ºF. Purple Raspberries: Floricane/Summer-bearing - Brandywine -25ºF; Estate -25ºF; Royalty -25ºF. For the following: Zone noted is the northernmost zone in which fruit is likely to mature before fall frost. Red or Yellow Raspberries: Primocane/Fall-bearing - Amity Zone4; Autumn Bliss Zone3; Bababerry Zone6; Goldie Zone5; Heritage Zone5; Redwing Zone3; Ruby Zone5; Summit Zone3.
Zone noted is the northernmost zone in which fruit is likely to mature before fall frost.
Blackberries: Thorny (Erect) - Brazos Zone7-8; Cherokee Zone5; Cheyenne Zone6; Choctaw Zone6; Darrow Zone5; Illini Hardy Zone4 (-20ºF); Shawnee Zone6. Thornless (Erect) - Arapaho Zone6; Chester Zone5 (-10ºF); Dirksen Zone5; Hull Zone5; Navaho Zone5. Western Trailing Blackberries - Lose their buds at temperatures below 15ºF: Marion; Olallie; Evergreen; Boysen (Boysenberry); Logan (Loganberry); Kotata; Sunberry; Tayberry; Tummelberry.
R. arapaho; Thornlass Blackberry
R. biflorus & R. lasiostylus are commonly called Ghost or Whitewashed Brambles because of their pretty, white stems;
R. Fockeanus; R. reflexus; R. chamaemorus (Cloudberry). The fruits of most of these ornamental varieties are bitter and inedible.
R. deliciosus (Boulder Raspberry);
R. illecebrosus (Strawberry Raspberry);
R. leucostachys (Broadleaf Evergreen Blackberry);
R. parvifolius (dwarf);
R. phoenicolasius (Wineberry);
R. procerus (Himalaya Berry);
R. Linkianus (double, white flowers);
R. trivialis (Southern Dewberry);
R. spectabilis (Salmonberry);
R. ulmifolius bellidiflorus (double, rose-red flowers);
Go see DICTIONARY OF BOTANICAL NAMES.
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