Mulberry

Morus nigra

Morus alba

Introduction: The Mulberry is native to western Asia, but had spread to Europe by the time of the ancient Greeks. The fruit is excellent when fully ripe, but too soft to be a useful commercial fruit.

Nutrients: Dried mulberries are a substantial food source, somewhat comparable to figs in nutritional value.

About

Ease of growing:

Hours of winter chill 3

Size 15-30 ft tall x 15-30 ft wide

Zones: 5-10

Blooming period: Early summer

Fruiting period: Mid to late summer

Chill requirements: 400 hrs

Bearing age: 2-3 years

Spacing: 15-40 ft apart

Climate: Mulberries are naturally adapted to grow in hot dry summers and cold winters, but they are quite adaptable and will grow in most places.

Site: The trees need full sun for best productivity, but will also tolerate some shade.

pH 6.5 – 8.0

Soil: Mulberries will grow in most soils, but do best on a fertile one.

Planting:

When: Obviously you can only plant when trees are available, which usually means in winter or early spring for bare root trees (though some people prefer to plant in autumn, while the soil still holds some heat). In cold climates bare root plants are usually planted in spring. In mild-winter areas they may be planted nay time between late fall and early spring.

Plants in containers can be planted at any time of year, but are more expensive and don’t usually do as well (sometimes they are simply left over bare root stock that has been potted up).

How: Dig the planting hole 2‑3 times as wide as the root ball, to give the roots plenty of loose soil to grow into. You want the hole to be the same depth as the root ball (or roots if bare root), so it can be set into the ground at the same depth it was growing in the nursery. This is most easily measured by laying a stick across the hole to get the right height. The graft union should be 3-6” above the soil.

In poorly drained soils you may have to plant on a mound, to keep the collar of the tree from staying wet for long periods (too much water could cause it to rot).

Start planting by throwing a couple of shovels of soil (possibly mixed with some organic matter if the soil is poor – to help it hold moisture) into the bottom of the hole. Make this into a slight mound and then spread the roots out evenly over it. You then put some soil in the hole to anchor the tree in place and firm it down. Then re-fill the hole with the rest of the soil (make sure the tree remains vertical). You may also want to add some rock phosphate to the soil as you go.

When you have finished planting the tree should be on a slight mound, so as the soil settles it becomes flat. If it starts out flat it may end up as a slight depression where water can collect (which can be a problem on poorly drained soils).

You then water the tree thoroughly, not only to supply water to the plant, but also to settle the soil and establish contact between roots and soil.

The final step is to spread out a mulch to conserve water, and keep down weed competition (keep this six inches away from the trunk).

It is also a very good idea to put a permanent label on the tree saying the variety and rootstock (and write it down in your garden journal).

Support: Newly planted trees were once routinely supplied with a stake to support them, but it is now thought that trees become stronger more rapidly if not staked. Staking is only usually necessary on very windy sites (especially for dwarf trees which grow on weak rootstocks).

Protection: If gophers live in your area you will have to plant your trees in gopher wire baskets (I make my own to whatever size I need). If other rodents are a problem (they may chew on the bark, stunting or even killing the tree) you may have to use various kinds of metal or plastic mouse guards. These should go several inches into the ground and should have gravel around them to deter digging.

Spacing:

Maintenance: I have found mulberries to be very trouble free and mine gets no attention at all except at harvest time.

Fertilizing: Not usually necessary.

Watering: Established trees are very drought tolerant and rarely need watering.

Pollination: Trees are self-fertile.

Pruning Mulberry is terminal bearing, which means they produce fruit at the end of new growth. They don’t usually require much pruning.

Propagation: Mulberry is easily grown from softwood or hardwood cuttings and can grow into a productive tree surprisingly quickly. It can also be grown from seed, but this is slower and some trees will probably be fruitless males. Special cultivars are sometimes budded on to seedling rootstocks.

Containers:

Mulch: A mulch of compost or aged manure is useful, as it keeps the soil moist, keeps down weeds and supplies nutrients.

Pests: Birds are the main problem when growing mulberries as they adore the fruit, and if given the opportunity will stay around the trees until they have stripped them bare. Netting is the most effective solution, though it has to be pretty thorough as they will try to find a way in through any openings. Another possible approach is to string up bright flashing objects like shiny aluminum pie tins, mylar tape or old cd’s. You might also try inflatable predator balloons.

Caterpillars sometimes go for mulberries, including the silkworm, which live their whole lives on them.

Disease:

Harvest:

When: The fruit has a fairly long ripening period and may stay on the trees for months if birds don’t get to it. I like the fruit even when it is slightly under-ripe and tart. It gets sweeter when fully ripe (and very soft and mushy). If left on the tree for long enough it may even dry out completely, just like the related Fig. Dried mulberries are a very nutritious food and have been widely used in Afghanistan and neighboring countries.

How: You can start harvesting the fruit as soon as it turns dark purple, though it often disintegrates if you pull too hard. When this happens the abundant bright red juice often stains hands and clothes. If there is a lot of fruit you can try laying a sheet under the tree and shaking it.

Storage: Ripe fruit must be used promptly, as it doesn’t keep for more than a day or two (if you have a lot it can be made into preserves). Dried fruit can last for months.

Unusual growing methods

Ornamental uses: It isn’t a good idea to plant trees over paved areas as dropping fruit will stain them. Larger trees make great shade trees, casting cool, dense shade.

Rootstocks

Varieties

Food uses: Young leaves are edible and may be used like grape leaves.