Mulberry Tree
(morus alba, morus rubra, morus nigra…)
In a mulberry orchard, it is essential to choose a sunny location protected from strong winds to optimize fruiting. The soil should be deep, rich in organic matter and well-drained. A spacing of 5 to 7 metres between the trees promotes good aeration, limits excessive humidity and facilitates maintenance and harvesting.
– Location
Mulberry trees are hardy trees that adapt well to a variety of climates, but they prefer:
- Exposure: Sunny, with good sunshine to promote fruiting.
- Climate: Resistant to cold (some down to -20°C), they grow best in temperate and warm zones.
- Wind: They handle wind well, but a windbreak can be useful in case of strong winds.
– Ground
The mulberry tree adapts to different types of soil, but it prefers:
- Well drained: It does not tolerate waterlogged soils.
- Fertile and deep: Soil rich in organic matter will promote good growth.
- pH: Slightly acidic to neutral (pH 6–7.5).
If the soil is too compact, adding compost and sand can improve the structure.
– Supports (in case of trellised pipes)
Mulberry can be grown as a free tree, but some varieties (e.g. Morus nigra) can be trained to facilitate harvesting and management:
- Goblet or espalier
- pruning: To promote aeration and fruit production.
- Stakes: For young plants and varieties with a drooping habit.
- Trellising on wires or trellises: Possible for fruit hedge training.
– Spacing
The spacing depends on the pipe chosen:
- In the open field: 5 to 8 m between the trees, depending on the vigour of the variety.
- In fruit hedges: 2 to 3 m between plants.
- In espalier: 1.5 to 2 m on a structure
- Family: Moraceae
- Type: Deciduous tree (loses its leaves in winter)
- Height: From 5 to 15 m depending on the species and the management chosen
- Lifespan: Long lifespan, some specimens live for several centuries
- Habit: Variable depending on the species (spreading, erect, drooping)
– Growth
- Speed: Medium to fast (30 to 80 cm per year in favourable conditions)
- Development: Rapid growth in the first few years, then more moderate
- Adult size: Reached in 10 to 20 years depending on the species and growing conditions
- Twigs: Flexible and sometimes brittle, especially in young plants
– Flowering
- Period: Spring (April-May depending on the climate)
- Type of flowers: Discreet, in small elongated kittens
Monoecious (male and female flowers on the same tree) or dioecious (separate male and female trees) depending on the species - Pollination: Mainly anemophilic (wind)
Some cultivars are self-fertile, others require the presence of another tree for pollination
– Root system
- Type: Taproot and deep, but with many superficial secondary roots
- Adaptability: Good drought resistance when well established
- Effect on the soil: Powerful roots that can lift paving stones or damage nearby infrastructure
The individual management of the mulberry tree is based on training and maintenance pruning carried out in winter. Thinning the interior branches and removing dead wood creates airy and balanced branches. A vase or goblet-shaped management is often preferred to facilitate fruit picking.
– Education and training
The tree is formed in the first years to achieve a good balance between growth and fruit production.
- Free tree management (natural habit):
Leave a main trunk of 1.5 to 2 m before the first carpenter.
Select 3 to 5 well-distributed scaffold branches.
Promote an open structure for air circulation and light. - Cup driving:
Ideal for a more compact tree and easier harvesting.
Prune the young central spire and select 3-4 scaffold branches.
Prune regularly to avoid too much apical dominance. - Trellised pipe (espalier or fruit hedge): Possible on a wall or a support with wires. Cut in the shape of a palmette or in a horizontal cord to limit the clutter. Requires more frequent pruning to control vegetation.
-Pollination
Mulberry can be monoecious (male and female flowers on the same tree) or dioecious (separate male and female trees).
- Pollination method:
Mainly anemophilic (by wind).
Some varieties are self-fertile, but the presence of several trees can improve fruiting.
If the variety is dioecious, a male tree is needed nearby to ensure pollination of the females.
– Maintenance pruning
Regular pruning is essential to maintain the productivity and health of the tree.
- Training pruning (young tree, 1-5 years):
Limit the height and select the well-oriented branches.
Remove misplaced or competing branches. - Maintenance pruning (mature tree):
Remove dead wood and broken or misoriented branches.
Aerate the center of the tree to limit disease and improve light penetration.
Prune after harvest or at the end of winter (February-March). - Rejuvenation pruning (old or neglected trees):
Gradually reduce the height to revive growth.
Shorten old carpenters in several stages to avoid too much stress.
– Canopy formation
The aim is to achieve a balance between production, vigour and accessibility of the fruit.
- Wide and spreading canopy (free-form):
Allows for a heavier harvest but takes up more space.
Suitable for areas with a lot of space and few size constraints. - Compact and controlled canopy (cup or wall bars):
Ideal for small spaces or denser grows.
Facilitates maintenance and harvesting at human height. - Height control:
If the tree becomes too large, gradually fold down the central arrow.
A well-balanced tree must keep a good ratio between height and width.
The fruits of mulberry trees are distinguished by their sweet, sometimes slightly tart taste and juicy texture. Black mulberry, in particular, is renowned for its aromatic richness. The fruits, which come in clusters, vary in colour from white to dark red or black depending on the species, and are very popular both for fresh consumption and for processing into jams or juices.
– Appearance and Shape
Small compound fruits, reminiscent of blackberries.
Elongated (2 to 5 cm) and cylindrical.
Colour varies according to the species:
- Morus nigra: Black-purple, very juicy.
- Morus alba: White to pink, sweeter.
- Morus rubra: Dark red to purple, acidic.
Flavor and Texture
- Sweet to tart flavor depending on the species.
- Tender and juicy texture, sometimes slightly grainy.
- Very fragrant, with notes of honey, grapes or fig.
– Nutritional value
- Rich in antioxidants (anthocyanins, resveratrol).
- Good source of vitamin C and iron.
- Contains fiber, promoting digestion.
- Low in calories (about 43 kcal/100 g).
– Storage and Use
- Fragile, must be eaten quickly after harvest.
- Can be processed into jams, juices, wines, dried fruits.
- Ideal for pastries and desserts.
Although mulberry trees are generally hardy, it is important to watch for fungal diseases (such as leaf spot or rot) and insect pests (aphids, mealybugs). Good orchard hygiene, the removal of dead leaves and damaged fruit, as well as the occasional use of biological treatments (manure, natural fungicides) make it possible to limit phytosanitary risks.
-Monitoring
Regular observation can quickly detect the first signs of disease or pest attacks.
- What to watch for:
Appearance of spots on the leaves (powdery mildew, anthracnose).
Presence of mealybugs, aphids, mites under the leaves.
Abnormal deformities or yellowing of leaves.
Dead wood or fungus on the bark. - Frequency:
Weekly inspection during the growing season.
Reinforced observation in spring and late summer.
– Preventive treatment
The goal is to anticipate problems before they become serious.
- Natural strengthening:
Bring nettle or horsetail manure to strengthen the tree.
Use balanced organic fertilizers to avoid plant stress. - Disease prevention:
Treatments with Bordeaux mixture at the end of winter against fungal diseases.
Sulphur application in favourable conditions for powdery mildew. - Pest control:
Promote biodiversity (ladybirds, lacewings) against aphids.
Spray black soap in case of a beginner attack.
– Hygiene
Good environmental management limits the spread of disease.
- Disposal of contaminated parts:
Collect leaves and fruit that have fallen to the ground.
Burn or hot compost the diseased parts. - Disinfection of tools:
Clean pruning shears and saws after each pruning with alcohol or bleach. - Rotation and association:
Avoid planting too densely to limit the transmission of diseases.
Combine mulberry with repellent plants such as garlic or tansy.
-Ventilation
Aeration reduces humidity and limits the growth of fungi and bacteria.
- Adequate spacing between trees (5-8 m in open field).
- Regular size to clear the center and promote airflow.
- Avoid overwatering, especially on foliage.
- Grass management under the tree: Maintain light mulch or low ground cover to avoid excessive moisture.
Mulberry trees are harvested in the summer, usually from late summer to early fall. The fruits should be hand-picked when ripe – they come off easily and have a beautiful colour – to preserve their delicacy. Mulberry trees are best eaten fresh, but they are also suitable for various culinary preparations (jams, compotes, juices).
– Harvest period
- Season: From June to September depending on the species and climate.
- Morus alba: Early summer (June-July).
- Morus nigra and Morus rubra: Mid-summer to early autumn (July-September).
- Maturity indicators:
Well-coloured fruits depending on the variety (white, red, black).
Easily detachable from the shaft.
Tender and juicy texture, sweet flavor.
– Harvesting method
- Manual harvesting:
Gently pick the ripe fruit by hand.
Ideal for fresh consumption or small production. - Shaking harvest:
Spread a tarp under the tree and shake the branches.
Allows for faster harvesting, but the fruit is fragile. - Frequency:
The fruits do not all ripen at the same time → harvest spread over several weeks.
Harvest every 2 to 3 days to avoid losses to the ground.
-Conservation
At room temperature: 1 to 2 days maximum (very perishable).
- In the refrigerator:
In an airtight container, 3 to 5 days.
Avoid excessive humidity to limit mold. - Freezing:
Spread the fruit on a baking sheet to prevent them from sticking together.
Then, store them in an airtight bag (duration: 6 to 12 months). - Transformation:
In jam, juice, syrup, wine, dried fruit for longer storage.
Drying in a dehydrator or in the sun to obtain fruits concentrated in flavor.
