Trailing Blackberries

CULTURAL  REQUIREMENTS:  Blackberries will thrive on most soil types, but good drainage is desirable with most varieties.  Soils that are naturally fertile, easily worked and of good moisture holding capacity are the most suitable.  While not as cold hardy as the raspberries, many varieties of blackberries do well in large areas of Southwestern Idaho. We have listed below the varieties we feel do well in the Boise area. There are other varieties that perform well in the valley and new varieties seem to always becoming available.

Depending on the cultivar, blackberries ripen from mid-June to mid-October.  All types of blackberry plants are self-fruitful, so you need only plant one variety for pollination.  Blackberry plants are known to be a perennial, and the roots live for many years, however the canes are biennial, meaning that they grow one year and produce fruit the next.  Canes die after fruiting and should be removed at that time.  Blackberries require heavy staking, trellising and or fencing.

FERTILITY:  Blackberries respond extremely well with Ferti-lome “gardeners special” fertilizer when applied at blossoming time.  Blackberries also thrive on organic fertilizers such as Natural Guard’s “All Purpose” Plant Food.  Cowgirl sterilized steer manure is also a great product to use with blackberries.

            Good soil moisture should be maintained by irrigation at least for the first year after planting.  Fruit production will benefit if irrigation is practiced up until fall rains begin.

PLANTING INSTRUCTIONS:  Plant bare root plants about the same depth the plant grew at our garden center, covering any white sprouts arising from the crown.  Avoid wadding the roots in the planting hole, pruning them back if necessary. Avoid pruning of roots on thornless varieties as they may give raise to thorny suckers if so treated.  Always follow our planting instructions for best results on potted blackberry plants.  If you don’t have planting instructions, ask for your free copy at the time of purchase.

PRUNING AND TRAINING:  As the new canes begin growing along the ground in the spring, move them alongside the row from time to time to keep them out of harm's way until they are ready to be trained.  These canes will not bear fruit until the following summer when they are two years old.  Remove two-year old canes close to the ground as possible without damaging the new canes after harvest.

            Spring training is essential as canes left on the ground over winter are less apt to be damaged by freezing weather.  Train the new canes before the leaf buds begin expanding.  Several systems are used in training trailing blackberries.  The simplest for the home gardener is a stake with a cross arm about five feet high.  Canes should be brought up either directly from the ground or spiraled around the stake and held in place with two or three ties of strong twine.  Twine may not be necessary if canes are looped over the cross arm and the ends twined into the canes below.

            Various innovative methods of training are used with wire trellises.  The most common trellis has two wires, one wire at three feet and the other at five feet.  The canes to be trained are divided into two parts, and each taken separately to the top wire, and then the canes are brought down to the lower wire and turned back toward the plant with one or two twist.  Excess cane length can be removed.

THORNLESS BLACK SATIN:  Released on the East Cost and USDA tested.  These blackberries area large, firm and glossy.  They have a sweet flavor and excellent quality for jams, jellies, and fresh eating and pastries.  Black Satin berries produce heavy yields, are semi-erect and thornless.  The vines do not produce the occasional sticky cane like so many other thornless blackberry types.  This variety of berry is highly resistant to Septoria leaf spot, Anthracnose and tolerant to mildew.  They ripen in July.  A good variety of thornless blackberry for the Boise climate.

THORNLESS BOYSENBERRY:  Fruit on this juicy, sweet, full-bodied berry is quite large and almost seedless.  Great for jams, deserts, and fresh eating.  Matures in May to June of each year.

THORNLESS LOCKNESS:  Probably one of the best thornless blackberries for the home and garden.  This plant produces heavy fruit yields and is rated as the best tasting blackberry.  Ripens in July to August.

MARIONBERRY:  Its berries are large, bright black and excellent flavor.  We recommend them for fresh eating, jams, preserves, and desserts.  This berry is quite vigorous and thorny. It has strong canes.  The berry ripens in July and early August.  Marionberries produces smaller seed than Boysenberries.  Marion blackberries are very popular commercially.

SYLVAN:  Comes to us from Australia, but its parents are from the Pacific Northwest.  The berries are large, shiny and have a mild, very sweet flavor (has the wild Himalayan flavor.)  We feel this is the highest quality fruit we have seen.  Very similar in appearance to Marion, but much larger.  Sylvan is a bit firmer than Marion and ripens a few days earlier.  Sylvan berries are vigorous, thorny and produce trailing vines that are highly productive.  They are tolerant to heavy soils, wind and drought.