The mulberry tree is a medium-sized deciduous tree producing small, edible berries for six to eight weeks between June and July. Mulberry trees thrive in USDA zones 4 to 8, with rich, well-drained, moist soil that receives full to partial sunlight.
The red mulberry (M. rubus) and the white mulberry (M. alba) provide a habitat for birds and beneficial insects. The mulberry trees dark green leaves have serrated edges, the bark is orange-brown, and the May-blooming buds are dark and pointed. The flowers are small, green catkins.
White mulberries are the sweetest, while red and darker varieties are tart and sweet. The fruit is safe to eat. However, the leaves and unripe fruit and sap of mulberry trees can be mildly toxic to humans.
Growing a mulberry tree from seed is a rewarding endeavor that allows you to enjoy delicious homegrown mulberries within just a few years With patience and proper care, you can cultivate a productive mulberry tree in your own backyard.
An Overview of Mulberry Trees
Mulberry trees are fast-growing, deciduous trees that produce sweet, tangy berries reminiscent of blackberries. The trees thrive in warm climates and come in several varieties, including white, red, and black mulberries. They can grow over 50 feet tall at maturity but can be kept much smaller with pruning. Mulberry trees are most prized for their flavorful fruit, which can be eaten fresh or used in pies, jams, juices, and wines.
When to Plant Mulberry Seeds
The best time to plant mulberry seeds is in early spring after the last frost This gives the seeds time to germinate and become established before summer heat arrives Mulberry seeds require warm soil temperatures of at least 65-70°F to sprout. Plant them indoors 6-8 weeks before your last expected frost date.
Collecting and Storing Mulberry Seeds
To grow a mulberry tree from seed you first need to gather ripe mulberries when they are in season usually from June to August. Look for dark black or purple colored mulberries that have fallen from the tree, as these are fully ripe. Gently mash the berries to separate the seeds from the pulp. Rinse the seeds and allow them to dry fully on paper towels before storing. Place dried seeds in an airtight container in the refrigerator for up to a year before planting.
Stratifying the Seeds
Mulberry seeds have a dormancy period that must be overcome through a process called stratification before they will sprout. To stratify them, place seeds between damp paper towels in a sealed plastic bag. Refrigerate for 3-4 months, checking periodically to ensure towels remain moist. This mimics winter conditions and causes the seed coat to soften so moisture can penetrate for germination.
Planting Mulberry Seeds Indoors
Once stratified and ready to plant, fill small seed starting pots or trays with seed starting mix. Moisten the soil and plant 2-3 seeds in each pot, 1⁄4 inch deep. Keep the planted seeds warm, around 70°F, and keep soil moist but not saturated. Thin seedlings down to the strongest one per pot once sprouted. Let seedlings grow until they have 4-6 true leaves before transplanting into larger pots. Gradually acclimate them to outdoor conditions over 7-10 days before planting outside.
Transplanting Mulberry Seedlings
Young mulberry trees are ready to transplant into the garden after the final spring frost when daytime temperatures are consistently above 65°F. Choose a site with full sun or partial shade and fertile, well-draining soil. Dig a hole twice as wide and just as deep as the root ball of your seedling. Carefully remove from pot, loosen roots, place in hole, backfill soil, tamp down gently and water thoroughly. Stake the tree if needed for stability. Apply 2-3 inches of mulch around the base. Water seedlings regularly the first two years until well established.
Caring for Your Mulberry Tree
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Water seedlings frequently the first year or two, providing about 3 gallons per week. Mulberries are drought tolerant once established.
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Fertilize in late winter with aged compost or manure to maintain health.
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Prune only damaged or diseased branches in winter to shape. Avoid heavy pruning.
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Watch for pests like aphids and treat promptly to avoid spread.
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Weed and reapply mulch annually.
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Expect fruit in 5-10 years. Harvest ripe berries promptly when they fall to the ground.
Troubleshooting Mulberry Tree Issues
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If invasive saplings sprout, remove them promptly while small to prevent spread.
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If birds are eating fruit, net the tree when berries start ripening.
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If leaves are wilting, water more consistently, especially in droughts.
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If berries are dropping before ripe, ensure the tree gets adequate water.
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If berries are sparse, fertilize annually and prune minimally to encourage fruiting.
Final Thoughts
Growing a mulberry tree from seed takes time and patience but is a rewarding way to enjoy homegrown fruit. With proper seed stratification, care of seedlings, and attention as the tree matures, you can cultivate a thriving, fruit-bearing mulberry tree suited to your climate. Be sure to pick a variety that will perform well in your area for best results.
Plant a Mulberry Tree
Mulberry trees fend for themselves quite well once established, but here are things you can do to give them a good start.
- If you’re planting a container-grown mulberry tree, the first thing to do is look at the roots. Because mulberry is a vigorous grower, it’s common to find roots tightly wound around and knitted together.
- Use your fingers to tease apart the roots. We want the roots to grow outwards into the surrounding soil once planted, not continue to grow around in circles.
- Water well when first planted and until established.
Many sources suggest that regular pruning is not necessary with mulberry.
That’s fine if you want to feed the birds.
But if you’re growing the mulberries for yourself, I suggest a different approach: Be aggressive – and do it every year.
Your goal is to create a permanent scaffold of branches that you cut back to every year (see below).
Grow mulberry trees in an umbrella shape, so you can reach all of the fruit. Photo by Grimo Nut Nursery.
The best way to get a tree with a well-arranged scaffold is to make it yourself. Get a whip, which is a young, unbranched tree. (You probably won’t find this sort of tree at a garden centre; look for a specialist fruit-tree nursery.)
Then prune that whip so that it grows into a spreading tree. Think short and wide.
Start this pruning process by removing the “leader,” which is the growing tip of the tree. Linda Grimo, at Grimo Nut Nursery, a specialist nursery, suggests, “Stand as tall as you can with your pruners in your hand and clip off the top of the tree.” She explains that this stops it from growing upwards, and encourages the growth of side branches at a height you can reach without a ladder.
Umbrella-shaped mulberry tree in summer. Prune hard to keep berries at picking height. Photo by Grimo Nut Nursery.
Grimo says she likes to grow mulberry trees in an umbrella-shaped scaffold, with side branches (laterals) spaced out around the tree. For ease of getting under the tree to pick, don’t grow the side branches too low on the tree; her preferred height is just over a metre (4’) above the ground.
Mulberry trees growing in good soil put on a tremendous amount of growth every year. After formative pruning is complete, prune back almost all of the new growth every year, leaving just 1-2 buds from which the tree can send up replacement shoots.
This harsh pruning doesn’t affect cropping because fruit forms on new growth. “Don’t be afraid, you can’t kill a mulberry tree,” is what Grimo tells concerned first-time mulberry growers.
Prune in late winter, when dormant.
Mulberry Trees in Garden Design
Mulberry trees are quite versatile in garden design. Here are ideas for using mulberry trees in the landscape:
- Dwarf or weeping varieties are well-suited to use in small-space foodscapes
- Large, minimally pruned mulberry trees can be used for a canopy layer in a food forest
- Smaller mulberry varieties can fit a forest-edge niche in a food forest because the tree tolerates partial shade
- From a permaculture perspective, mulberry is an interesting option because along with fruit, it can provide poles and animal fodder (see below)
Starting Mulberry Trees from Seed
FAQ
How long does it take to grow mulberry from seed?
Growing trees from seed means that you don’t know what sex the seedlings will be until they flower. A seedling mulberry often takes from 5-10 years to begin flowering.
Why is it illegal to plant a mulberry tree?
Environmental Impact
White mulberry trees have been classified as invasive in certain regions due to their rapid adaptability and potential to spread extensively. Such invasive species can quickly dominate and outcompete native vegetation, leading to significant disruptions in local ecosystems.
Can you grow a mulberry tree from a mulberry?
- Mulberry trees are very easy to propagate from cuttings.
- Take cuttings from healthy, mature branches.
- Prepare the cuttings by removing some lower leaves and applying rooting hormone.
- Plant the cuttings in well-draining soil or potting mix.
- Keep the soil moist and provide a warm, humid environment.
- Once roots have developed, you can transplant the cutting into its permanent location.
How many years does it take for a mulberry tree to bear fruit?
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Seed-grown trees:These trees take the longest to reach fruiting maturity, typically 5 to 10 years.
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Grafted trees or cuttings:These trees, which are essentially clones of a mature fruit-bearing tree, can start producing fruit much sooner, sometimes within the second or third year after planting.
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Factors affecting fruiting time:
- Tree age and size at planting: Older or larger trees at the time of planting may start fruiting sooner.
- Cultivar: Some mulberry cultivars are known to fruit more quickly than others.
- Growing conditions: Optimal growing conditions, such as proper sunlight, water, and soil, can help accelerate fruiting.
- Tree age and size at planting: Older or larger trees at the time of planting may start fruiting sooner.