Germination temperature
Warm days and cooler nights: the standard seed test alternates 30 °C (86 °F) for 8 hours with 20 °C (68 °F) for 16 hours.
Fruit growing guide
White mulberry is a hardy, fast-growing fruit and fodder tree that grows from tiny seeds sown almost on the surface. This guide covers fresh versus stored seed, cold treatment, shallow sowing and raising seedlings to planting size.
Warm days and cooler nights: the standard seed test alternates 30 °C (86 °F) for 8 hours with 20 °C (68 °F) for 16 hours.
Barely covered. Press the tiny seed onto the mix and give it only a light dusting.
Usually 1-2 weeks after spring sowing of treated seed; fresh summer-sown seed about 2 weeks.
Half shade for the first few weeks after germination, then full sun.
None for fresh seed sown at once. Stored seed for spring sowing: 1-4 months of moist cold at about 1-5 °C (33-41 °F).
Raise in a seedbed or trays and plant out as one-year-old seedlings.
Seed is orthodox: the World Agroforestry database reports viability for several years in hermetic storage at room temperature, and the USDA Woody Plant Seed Manual stores mulberry seed at -23 to -18 °C (-9 to 0 °F). Keep packets dry and sealed. Seeds are tiny: sources give from about 517,000 (USDA average) to 1.1 million (World Agroforestry) seeds per kilogram.
Not needed. The USDA plant guide notes that some seeds have hard coats and dormant embryos, which is why fresh seed comes up unevenly, but moist cold treatment is the usual remedy rather than nicking such small seeds.
Recommended for stored seed sown in spring. Mix seed with moist sand or peat in a sealed bag and keep it in the refrigerator: the USDA manual gives 0.6-5 °C (33-41 °F) for 30-120 days and the USDA plant guide 1-3 months. Fresh seed sown straight from the fruit is usually not treated.
Not needed. Stratified seed is already moist, and fresh seed can be sown straight after cleaning from the fruit.
Warm, ideally with a day-night swing around 30 °C (86 °F) by day and 20 °C (68 °F) at night. In warm climates such as most of India, sow fresh seed when the fruit ripens; in cooler countries sow stratified seed in spring once days are warm.
Nurseries sow the seed so it is barely covered with soil. Scatter thinly on a level, firmed surface and cover with no more than a sprinkle of fine mix or sand.
A fine, free-draining seed mix. For the planting site, World Agroforestry describes deep, alluvial loam with good moisture and pH 6.0-7.5 as ideal, although the tree tolerates sandy to clay loams.
Keep the surface moist but not soggy until seedlings appear. US nurseries cover beds with straw, leaves or burlap until germination; in trays a clear cover does the same job.
Uncover as soon as shoots appear and give half shade for a few weeks, as both USDA sources advise, then move seedlings into full sun.
Spring-sown seed usually emerges in 1-2 weeks. Seed collected in early July and sown immediately reached 75% germination in one US trial, but only 12-50% of seeds typically become usable seedlings, so sow generously.
Grow seedlings on for a season. US nurseries lift one-year-old seedlings about 25 cm (10 in) deep for field planting. Roots are brittle, so lift with plenty of soil and plant in full sun in deep, moist, well-drained ground.
Water young trees through dry spells and keep weeds down. Shape the tree in the dormant season only, removing badly placed or dead branches; mulberries bleed sap if cut while it is flowing.
Cause: dormant or hard-coated seed, or seed sown too deep. Fix: stratify stored seed for 1-4 months, sow on the surface and keep it constantly moist.
Cause: full sun on tender seedlings or a dried-out surface. Fix: give half shade for the first few weeks and never let the seed tray dry.
Cause: powdery mildew, listed for mulberry by World Agroforestry and Guam extension. Fix: keep trees open by pruning so leaves dry quickly after rain.
Cause: several defoliating caterpillars recorded on Morus alba in India. Fix: inspect young trees regularly and remove larvae by hand while infestations are small.
Cause: birds eat the berries and spread the seed; the USDA notes white mulberry can become weedy. Fix: net fruiting trees, pick up fallen fruit and check local weed rules outside its native range.
Fruit production varies between individual trees. Grow several seedlings and keep the best croppers, or root cuttings from a good tree: the USDA plant guide uses 22-30 cm (9-12 in) cuttings with three buds, buried 6-9 cm (2.5-3.5 in) deep, with June and July the best rooting months.
World Agroforestry records white mulberry from sea level to 3,300 m, so it suits both the Indian plains and the hills.
Sources differ on drought: the USDA calls established trees drought tolerant, while World Agroforestry calls the species highly susceptible to drought. Water young trees regularly and mulch in dry seasons.
Prune laterals lightly to keep the tree short and open; fruit is easier to pick and leaves dry faster after rain.
Sow white mulberry seed on the surface of a moist tray for a hardy fruit tree that suits plains and hills alike.
Fresh seed sown straight from ripe fruit usually does not. Stored seed sown in spring germinates better after 1-4 months in moist sand or peat at about 1-5 °C (33-41 °F).
Not necessarily. Fruit production varies from tree to tree, so seedlings are best treated as new trees; to copy a particular tree, grow it from cuttings.
Seedlings take longer than cuttings. Guam extension reports that cutting-grown trees can fruit in 1-2 years; seedlings usually need several more years of growth.
Barely cover it. The seed is tiny, and nurseries sow it so it is just covered with soil, then keep the bed mulched and moist until it germinates.