How to Grow Wonderberries USA | Complete Growing Guide

At a Glance

Quick Facts

Factor	Value
Soil pH	6 - 7.5
Sunlight	6-8 hours direct sun
Soil texture	Light (sandy), medium (loamy) or heavy (clay) (PFAF)
Drainage	Fertile, well-drained preferred (PFAF)
Lifecycle	Grown as an annual outside the tropics; killed by frost (PFAF; University of Illinois Extension).
Edible parts	fruit

Soil & Growing Conditions

Water: Prefers moist soil (PFAF)

Soil pH range

6 7.5

Span reflects genuine variation between the cited authorities, not a single agreed figure.

Growth Stages

Stage	BBCH	Notes
Sowing and establishment	0	Sow seed under cover/indoors in spring; transplant out only once frost danger has fully passed -- treat much like a tomato (PFAF; University of Illinois Extension).
Vegetative growth	3	Bushy, upright-branching growth; needs full sun and a fertile, well-drained, consistently moist soil (PFAF). Watch closely for tomato hornworm -- a University of Illinois Extension trial found a severe infestation (55 caterpillars hand-collected) on this crop.
Flowering	6	Small white flowers, produced in quantity once established -- one University of Illinois Extension trial plant recovered from pest damage to produce "several hundred" flowers.
Fruiting and harvest	8	Small (about 1cm) dark blue-purple fruits form in clusters (PFAF). Only pick and eat fully ripe (dark) berries -- green, unripe fruit is poisonous (University of Illinois Extension; PFAF).

Harvest & Storage

When to pick: Pick only fully ripe, dark blue-purple berries -- green, unripe fruit is poisonous and reactions to it vary by individual (University of Illinois Extension). Ripe fruit is soft and juicy with a mild, bland, slightly sweet flavour; not very appetizing eaten raw, and best used cooked into jelly, jam or pie filling (PFAF; University of Illinois Extension).

Pests

Hornworms

high

Manduca spp.

A University of Illinois Extension field trial recorded a severe infestation -- 55 hornworm caterpillars hand-collected from the planting, alongside five-spotted hawk moths (the adult form) -- before the crop recovered…

Wonderberry Photo Gallery

Wonderberry plant in flower

A wonderberry plant with a white flower and hairy leaves.

Flower detail

Close-up of a white wonderberry flower with a yellow center and green fruit forming beside it.

Ripe berries

A bowl of ripe, dark purple wonderberries.

Unripe fruit cluster

A cluster of unripe green wonderberries on the plant -- these are poisonous and should not be eaten.

Leaf detail

Wonderberry leaves on a stem.

Plant in the wild

A wonderberry plant growing in the wild.

Ripe fruit on the plant

Ripe, dark wonderberries hanging on the plant.

Potted plant

A potted wonderberry plant with flowers and buds.

Flower with young fruit

A wonderberry flower with small fruit forming.

References

1. Plants For A Future (PFAF) - Solanum retroflexum (sunberry)

   Annual, spring-sown under glass, planted out after last frost. Soil: light/medium/heavy, mildly acid to mildly alkaline, prefers fertile well-drained. Full sun required, prefers moist soil. Fruit about 1cm diameter in small bunches. Edible: fruit only, raw or cooked (improved by cooking); many Solanum members have poisonous leaves and sometimes unripe fruit too. Native to Ethiopia, South Africa, Tanzania and other African countries.

2. University of Illinois Extension - The quest of growing wonderberries

   Solanum burbankii (synonym used in this source). Annual in zone 6, cannot tolerate frost; started indoors, transplanted after frost danger passed. Bushy, elevated growth habit, small white flowers. Trial in open garden and high-tunnel raised bed. Real trial finding: severe tomato hornworm infestation (55 hand-collected) plus five-spotted hawk moths present; recovered with more watering/monitoring to produce hundreds of flowers and berry clusters. Toxicity: green berries poisonous, do not pick green, ripe berries safe. Taste: soft, juicy, mild/bland, best as jelly/jam/pie filling. No final verdict reached on community-garden suitability.

2 independent sources are cited for this crop. Where they disagree - soil pH is the clearest case - every figure is preserved rather than averaged into false precision.