Guide to Growing Mulberry Trees

Mulberry trees are not only a beautiful addition to your landscape but also a rewarding fruit source. Whether you’re an experienced gardener or just starting out, this guide covers everything you need to know about growing mulberry trees—from selecting the right species and cultivars to best practices for planting, care, and harvest.

Why Grow Mulberry Trees?

Mulberry trees have long been admired for their delicious fruit, attractive foliage, and adaptability to various climates. With dozens of species and cultivars available, choosing the right tree can seem overwhelming. This comprehensive guide will demystify the world of growing mulberry trees, explaining key differences between species, providing practical care tips, and helping you choose cultivars best suited for your climate and taste preferences.

Understanding Mulberry Species and Cultivars

The Diversity of Mulberry Species

The genus Morus encompasses many species. However, for fruit production and ornamental purposes, only a handful are commonly grown. The most popular include:

• Morus alba (White Mulberry)
• Morus rubra (Red Mulberry)
• Morus nigra (Black Mulberry)
• Morus macroura (Himalayan or Long Mulberry)
• Hybrids – Many commercial cultivars are crosses between these species

Despite the plethora of names listed in botanical databases, only a few species are widely accepted for their fruit quality. For example, while the “Kew Plant List” may list over 200 names under Morus, only a fraction are recognized as accepted species.

Common Misconceptions About Growing Mulberry Trees

• Fruit Color Doesn’t Define the Species:
  White mulberry trees (Morus alba) can produce fruit ranging from white and lavender to black. Similarly, red mulberries (Morus rubra) often turn a deep red or almost black upon ripening.
• Mislabeled Cultivars:
  It’s not uncommon to find trees sold under popular names (e.g., ‘Dwarf Everbearing’ or ‘Gerardi’) that are mistakenly marketed as Morus nigra. Always verify species information with reputable sources or local experts.
• Hybrid Confusion:
  Many popular cultivars may be hybrids rather than “pure” species. Genetic testing often reveals that cross-species hybrids are common, so focus on the tree’s performance and fruit quality rather than strictly on its taxonomy.

In-Depth Look at Popular Mulberry Species

Morus alba (White Mulberry)

Overview:
White mulberry is the most widely grown species and boasts the greatest number of cultivars. Although its name suggests white fruit, many Morus alba cultivars produce pink to black fruit with a distinct flavor profile. Some white-fruited varieties even have a taste reminiscent of watermelon.

Growing Conditions:

• Sunlight: Requires at least 4 hours of full sun daily.
• Soil: Tolerant of poorer and drier soils; prefers a soil pH less than 7.5.
• Size & Lifespan: Can grow up to 70 feet tall and live for 250 years.
• Elevation: Thrives at elevations up to 10,000 feet.

Morus rubra (Red Mulberry)

Overview:
Native to North America, red mulberry trees (Morus rubra) produce fruit that is typically deep red before turning reddish-black. Their flavor is often described as more “flavorful” and tart compared to white mulberries.

Growing Conditions:

• Sunlight: Performs best in full sun, although it tolerates partial shade.
• Soil: Prefers moist, organic-rich soils and can handle a wide range of soil types up to a pH of 8.5.
• Resilience: Once established, red mulberries can survive both drought and extended flooding.
• Size: Generally grows to a maximum height of around 70 feet.

Cultivation Tips:
Red mulberry trees tend to fruit on individual branches, so they are often best enjoyed when the fruit is still bright red. They are commonly grown from seed or grafted, as they do not root well from cuttings.

Morus nigra (Black Mulberry)

Overview:
Black mulberry (Morus nigra) is prized for its large, juicy, and highly flavorful fruit. Unlike other species, M. nigra is highly polyploid, meaning it has many sets of chromosomes. This characteristic may reduce the number of distinct cultivars, but the fruit quality remains outstanding.

Growing Conditions:

• Soil: Can tolerate more alkaline soils than other mulberry species.
• Sunlight: Requires full sun for optimal fruiting.
• Climate: Prefers a Mediterranean-type climate and is best suited to USDA Zones 6–9 (mainly west of the Mississippi).
• Size & Lifespan: Grows up to 45 feet tall and can live 500 years or more.
• Elevation: Thrives at elevations up to 6,500 feet.

Morus macroura (Himalayan or Long Mulberry)

Overview:
Often referred to as the Himalayan or long mulberry, Morus macroura produces fruit that can exceed four inches in length. Some cultivars, commonly called ‘Pakistan’ or ‘Shahtoot’ (meaning “King Mulberry”), are celebrated for their unique raspberry-like flavor and firm texture.

Growing Conditions:

• Climate: Does best in hot, humid climates; primarily recommended for USDA Zones 9 and 10, though some cultivars can survive in Zone 8 with proper care.
• Soil: Adaptable to a wide range of soil types, including heavy clay.
• Resilience: Highly disease resistant but may suffer from late freezes after bud break.

Mulberry Hybrids

Many mulberry trees available today are hybrids—often crosses between Morus alba and Morus rubra, or between these and Morus macroura. These hybrids can combine the best traits of each species, such as improved flavor, hardiness, and extended fruiting periods. As genetic testing continues to evolve, expect more refined classifications and an expanding list of hybrid cultivars.

Choosing the Right Mulberry Cultivar for Your Climate

When selecting a mulberry tree, consider the following factors:

• USDA Plant Hardiness Zone: Ensure the cultivar matches your local climate. For example, many true Morus nigra trees do not perform well in colder climates.
• Climate Challenges: If your area experiences early warm spells followed by hard freezes, opt for cold-hardy cultivars such as ‘Silk Hope’ or ‘Illinois Everbearing’ that delay bud break.
• Taste Preferences: Sample local trees when possible. Mulberry flavor can vary significantly based on soil, climate, and care.
• Tree Size and Management: Decide if you prefer a small, pruned tree for limited space or a larger tree that produces abundant fruit despite potential wildlife competition.

Growing Mulberry Trees – Care and Maintenance

Planting and Site Selection

• Sunlight: Choose a location that receives at least 4–6 hours of direct sunlight daily.
• Soil: Mulberries are adaptable but perform best in well-drained soils with a pH below 7.5.
• Space: Consider the mature size of the tree. For a heavy fruit crop, allowing ample space will help reduce competition with birds and pests.

Watering and Fertilization

• Watering: Regular watering is essential during the establishment phase. Once mature, most mulberry species are drought tolerant.
• Fertilization: Mulberries need minimal fertilization once established. Organic compost or balanced fertilizer applied in early spring supports healthy growth.

Pruning and Pest Management

• Pruning: Regular pruning promotes better air circulation and light penetration. Note that “everbearing” varieties produce a concentrated burst of flowers and fruit, which may require strategic pruning to prevent overcrowding.
• Pests: Birds, insects (such as thrips and fruit flies), and disease can affect mulberry yield. Consider protective measures like netting for small trees and monitor regularly for pest activity.

Growing Mulberry Trees – Tissue Culture Method

Tissue culture propagation produces disease-free plants, although they may take longer to bear fruit and reach full size. Currently, some cultivars (e.g., ‘Dwarf Everbearing’, ‘Pakistan’, and ‘Trader’) are available through tissue culture techniques. This method can be a great option for ensuring a healthy start to your orchard.

Mulberry Tree Roots: Invasiveness and Management Considerations

While mulberry trees are prized for their ornamental beauty and delicious fruit, it’s important to note that many species develop vigorous root systems. Here are some key points to consider regarding the invasiveness of mulberry roots:

• Vigorous Growth:
  Mulberry trees, especially species like Morus alba and Morus rubra, can produce extensive root systems that spread widely in search of nutrients and water. In some cases, these roots can be aggressive and may compete with nearby plants or invade unwanted areas.
• Potential Risks:
  The expansive roots may cause damage to nearby sidewalks, driveways, foundations, and underground utilities if the tree is planted too close to these structures. Proper planning and planting distance are essential to avoid future complications.
• Planting Guidelines:
  • Distance: When planting a mulberry tree, ensure it is set at a safe distance from hardscaping elements. A general rule is to plant the tree at least as far from a structure as the expected canopy spread at maturity.
  • Location: Consider planting mulberry trees in areas where there is ample space for the roots to expand without interfering with buildings or underground infrastructure.
• Management Techniques:
  • Root Barriers: Installing physical root barriers can help contain the spread of the roots and protect nearby structures.
  • Regular Maintenance: Routine monitoring and maintenance, such as periodic pruning or root trimming (if necessary), can help manage the tree’s root system.
  • Soil Management: Maintaining healthy soil and proper irrigation can sometimes help moderate overly aggressive root growth.
• Species Variability:
  Not all mulberry species are equally aggressive. For example, while Morus nigra tends to have a slower growth rate and more compact root system, other species like Morus alba can be more invasive. Knowing the specific characteristics of the cultivar you choose can help you plan accordingly.

Harvesting and Using Mulberries

Optimal Harvesting Techniques

Mulberries ripen gradually over several weeks, giving you plenty of time to pick the fruit at its peak. For the best flavor and texture:

• Timing is Key: Harvest the berries when they are firm, fully colored, and slightly glossy. Avoid waiting too long, as overripe fruit can become overly soft or ferment.
• Gentle Handling: Use a pair of scissors or garden shears to snip off clusters, or gently pluck individual berries to prevent bruising.
• Multiple Harvests: Due to staggered ripening, plan for several rounds of harvesting throughout the season to ensure you enjoy the freshest fruit possible.

Smart Storage Solutions

Proper storage is essential for extending the life of your mulberries and preserving their vibrant flavor:

• Refrigeration: Store fresh mulberries in a shallow container in the refrigerator, where they can last for up to 3–5 days.
• Freezing: Mulberries freeze exceptionally well. Lay them out on a baking sheet to freeze individually before transferring them to airtight freezer bags. This method helps preserve their texture and flavor for smoothies, jams, and desserts.
• Drying and Preserving: Consider drying mulberries or making preserves to enjoy their taste year-round. Properly dried mulberries make for a nutritious snack or a delicious addition to cereals and baked goods.

Creative Culinary Uses

Mulberries offer a burst of natural sweetness and tartness that can enhance many dishes:

• Fresh Eating: Enjoy them straight off the branch as a refreshing snack or mix them into fruit salads for an extra burst of flavor.
• Baking and Desserts: Use mulberries in pies, tarts, muffins, and cakes. Their unique flavor adds depth to baked goods, while their vibrant color makes for an appealing presentation.
• Jams, Sauces, and Smoothies: Mulberries are perfect for making homemade jams or sauces that complement meats, cheeses, or breakfast items. They also blend beautifully into smoothies, offering a nutritious boost to your daily routine.
• Creative Recipes: Experiment with mulberries in savory dishes, such as incorporating them into salads or glazes, to explore their versatility beyond sweet recipes.

Where to Buy Quality Mulberry Trees

• Local Nurseries: Purchasing from local growers can increase the likelihood of obtaining trees that are already acclimated to your climate. Always taste test if possible.
• Reputable Sources: Look for vendors who provide detailed information about cultivar performance, USDA Zone compatibility, and proper labeling to avoid misidentification.

Conclusion

Growing mulberry trees can be a highly rewarding project—providing you with ornamental beauty, delicious fruit, and a fascinating glimpse into horticultural diversity. By understanding the differences among species, choosing the right cultivar for your climate, and applying proper care techniques, you can enjoy a thriving mulberry orchard for decades.