There are three types of mulberry tree: the American (red) mulberry, black mulberry and white mulberry. They are all deciduous and grow between 30 and 70 feet tall, depending on the species. Mulberries need full sun and well-drained soil to thrive. Pruning helps them keep a good shape. It also opens the tree to sunlight and air circulation, which cut down on insect infestation and nourish the tree.
Develop a main set of branches when mulberry trees are young. Choose three or four branches to form the first scaffold whorl, or set of branches. They should grow on opposite sides of the main trunk of the tree, without being too close or directly opposite each other.
Prune lateral branches (branches that grow from the mulberry tree trunk) down so that each has 6 leaves. Do this annually in July to develop growth near the main branches.
Trim off dead, disease or weak branches. They may spread disease throughout the mulberry tree. Because they are already weakened, they are likely to snap off on their own, anyway. Make the cut where the unwanted wood touches healthy wood.
Cut branches that are overcrowded in the mulberry tree's canopy. Cut off those that are crossing or rubbing against each other. The goal is to allow more sunlight into the middle of the tree.
Remove shoots that grow at the base of the mulberry tree trunk. These will grow quickly and haphazardly, sucking water and nutrients from the rest of the tree.
Treating Sooty Canker Fungus
Sooty canker fungus is a common disease of the mulberry tree. It first becomes evident on the upper area of the tree’s main branches and the tree limbs themselves. Infected branches should be removed whenever signs of the disease appear, according to the Cooperative Extension Service at the University of Nevada. That treatment should only be used during a tree’s dormant period. Proper mulching and irrigation also go a long way in preventing canker-causing diseases.
Treating Leaf Fungi
Mulberry tree leaves can be infected by either Cercospora moricola or Cercosporella mori. Each causes reddish-brown spots and can cause excessive damage during rainy weather, according to the Cooperative Extension Service at Oklahoma State University. Once leaves have become infected, the most common treatment is to allow the leaves to fall, gather them and then burn the infected leaves.
Treating with Fungicidal Spray
Fungicidal sprays offer an alternative to treating leaf fungi diseases. They are especially effective on heavy infestations during the spring, which can severely damage a tree and reduce the production of leaves and fruit. To be most effective, fungicides should be applied before and during an infection. Once used, fungicidal sprays must be reapplied to prevent future outbreaks.
Purchase a fruit eliminator spray from any garden center. These specialty sprays are comprised of hormones that prevent the tree from producing fruit.
Wait until early spring when the mulberry tree has produced flowers, but not yet produced fruit. You can also spray as soon as you see an abundance of flowers buds that have not yet opened.
Use a thermometer to ensure that the daytime temperature is between 60 and 90 degrees F.
Pour the fruit eliminator solution into a garden sprayer and mix with water per the manufacturer's instructions.
Spray the fruit eliminator solution onto the leaves of the mulberry plant until it is completely saturated. Concentrate the application on the flowers and flower buds of the tree as this is where the fruit develops.
Mulberry Bible References
The author of 1 and 2 Samuel in the Hebrew scriptures refers to trees in 2 Samuel 5:23 and 24. Bible versions vary regarding the type of tree. According to the King James Version, the Lord instructed David to approach the Philistines in battle and to "listen for movement in the tops of mulberry trees."
Balsam Bible References
Other Bible versions, such as the Revised Standard Version, translate the mulberry tree in 2 Samuel and in Psalms 84:6 as baca or balsam trees, Balsamodendron opobalsamum. Balsam trees have never grown in Israel, and the passages may refer to the acacia tree, Acacia nilotica, according to Bible History Online.
Black Mulberry Bible References
The Revised Standard Bible includes a reference to mulberry trees in 1 Maccabees 6:34, written long after the books of Samuel. Because the King James Bible canon does not include 1 and 2 Maccabees, scholars do not address differences in translations. The 1 Maccabees passage to the mulberry tree may refer to the fruit, according to Bible History Online. Ancients cultivated black mulberries, or Morus nigra, all over Israel.
Reduce the height of your weeping mulberry by cutting down the top of your tree each year. When possible, you should start controlling the height of your tree before it is fully mature. It may be difficult to reach the top of mature mulberry trees.
Trim any branches that are touching the ground. Also, prune branches that are rubbing against other branches. Ideally, there should be 2-3 inches between branches at the top of the tree. This encourages air circulation and helps prevent disease.
Wait until the tree becomes dormant to perform heavy pruning. Weeping mulberry trees are prone to bleeding at cutting sites, but this is less likely to occur during dormancy.
Prune lateral branches in mid-summer to encourage spurs near the main tree branches. Avoid making cuts greater than 2 inches in diameter, as these will be slow to heal.
Remove dead, damaged, or diseased branches annually. Look for signs of insect infestation and remove affected branches. Burn diseased or infested branches to prevent contamination of other trees.
Prune the mulberry after all the leaves fall off, when the tree is dormant and less susceptible to disease, and before buds appear.
Sterilize pruning shears. Go over the blades with a rag dipped in rubbing alcohol.
Prune back branches of the tree when it is young to keep them from drooping and to maintain shape. Cut these branches right outside a node, where the branch swells and leaves attach.
Cut broken, dead and diseased branches just outside the root collar, where the branch attaches to another branch or the trunk. Remove crossing branches to increase air flow through the tree.
Prune off any low-hanging or otherwise inconvenient branches in winter, for best results, although any time of year is acceptable.
A white mulberry tree cultivar, weeping mulberry (Morus alba 'Pendula") is a dwarf tree growing 6 to 10 feet high. Its gnarled branches--with glossy green foliage, white summer flowers and edible fruit--bend to the ground. A weeping mulberry at Ottawa's Experimental Farm is more than 100 years old.
The species of the mulberry are white (Morus alba L.), American or red (M. rubra L.) and black (M. nigra L.). There are also many hybrids from the red and white species.
While all species of mulberry can be grown in warm climates, only a few fare well in cold climates. In the United States, red mulberries are hardy to subzero temperatures and white cultivars to zero temperatures. Black cultivars thrive in warmer hardiness zones.
The fruit from the red trees are a deep red, almost black color when they are ready to be picked. The black mulberries are ripe when they turn from red to black. The white mulberries stay white and are ripe when they become plump and juicy.
Red and white mulberries may be harvested in late spring. Black mulberries ripen in late summer. To harvest, spread a sheet on the ground and then shake the tree or individual limbs.
The mulberry isn't a true berry; it is an aggregate fruit. It is made up of many drupes, which are individual fruits.