How to Grow Red Mulberry Trees

Vibrant Red Immature Mulberry Fruits Ripening on the Tree


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Mulberry trees have been important in cultures worldwide for centuries. The genus has been used for wood, textiles, food, drink, and aesthetics. Though there are 16 genera from across the globe, there is only one mulberry native to North America, Morus rubra, the red mulberry tree.

Today, the red mulberry tree is an uncommon sight in both the natural landscape and the nursery trade. It has been overtaken by the invasive White Mulberry, which outcompetes and hybridizes with the Reb Mulberry. When used in garden design, the red mulberry is chosen for its ornamental value and, occasionally, its delicious fruit often used in jams and pies. 

This fruit that makes the tree so attractive is also one reason people shy away from using it in their landscapes. After falling, the crushed fruit is notorious for staining the landscape and anything in the area under its canopy—unfortunately, the immediate area not the only spot at risk. Birds love the fruit and deposit their droppings, which are brightly colored around the area. Red Mulberry is a fantastic tree for feeding wildlife, but this species might need to be overlooked if cleanliness matters.

If looking for the aesthetics, form, and size of a red mulberry without the mess, consider one of the numerous fruitless M. alba cultivars available in the nursery trade. Two other benefits of looking towards these fruitless cultivars are that the trees will not hybridize and spread, and the M. alba cultivars are readily available in the nursery trade.

Whether choosing the tree because it is a native and the idea of fresh berries is enticing, or the grand spreading shade tree’s pendulous red fruit is attractive to the eye, the red mulberry deserves closer inspection.  

Botanical Name  Morus  rubra
Common Name Red Mulberry 
Plant Type Tree
Mature Size 35 to 50 Tall 30 to 40 Wide
Sun Exposure Full Sun to Part Shade
Soil Type Rich, Moist, Well-drained
Soil pH  Neutral to Basic 
Bloom Time March to April
Flower Color  Green
Hardiness Zone  4-8, USA
Native Area  Eastern United States 

Red Mulberry Tree Care

If planted and attended to with some affection, the red mulberry tree is a beautiful, large, stately species that can produce a bountiful harvest of berries. 

Site selection will be an important aspect of the mulberry’s success. It is a large tree in height and spread. Consider a spot that will not just fit the tree now but 15 years in the future. Think about how the tree will interact with the infrastructure and hardscaping. The red mulberry’s messiness makes this step especially important to avoid staining and property damage from falling fruit.

When ready to plant, place the tree in a hole as deep as the container or ball and burlap and two times the width. Mulch around the newly planted tree out to the dripline, ensuring not to touch the bark, helping the newly planted tree retain moisture. 

Light

The tree will be its showiest and produce the most fruit when placed in full sun. It does tolerate part shade somewhat well but will not produce as proficiently.

Soil

To ensure success, place the red mulberry tree in well-draining conditions that are moist and rich. A loamy soil that is neutral to alkaline is preferred.

Water

Other than when first planted, there is no need to worry about supplemental watering. Initially, it is necessary to water the newly planted tree weekly. A thorough soaking is adequate. A good rule to go by is ten gallons of water for each inch of the trunk diameter. Weekly watering only needs to be maintained for the first year until roots are established. 

The red mulberry tree is drought-resistant, but it would be best if you still watered them to keep the soil around them from drying out during a drought. That way good fruit production will be more likely.

Temperature and Humidity

The species is a hardy tree with a range covering most of the United States east of the great plains. The red mulberry does well at a variety of temperatures. Its USDA Hardiness Zones are 3-8.

Fertilizer

There is no need to fertilize the red mulberry tree. It will do well in most soils, but increasing the yield of berries can be achieved by applying a 10-10-10 slow-release fertilizer every spring.

Is the Red Mulberry Toxic?

Unripe fruit and milky sap from all parts have low toxicity if eaten. Symptoms include hallucinations and stomach upset. The ripe fruit is, of course, non-toxic and delicious. The berries have been used to make wine, jellies, pies, and a food flavoring additive for centuries.