Light:

Hibiscus metabilis ‘Rubrum’ thrives in full sun, but it can tolerate partial shade. To encourage the best flowering and color, aim for at least 6 hours of direct sunlight each day.

Soil:

This hibiscus prefers well-draining, fertile soil with a slightly acidic to neutral pH (around 6.0 to 7.0). Adding organic matter like compost can improve soil structure and moisture retention.

Watering:

Water regularly to keep the soil consistently moist, especially during hot, dry spells. Once established, it can handle brief periods of drought, but it’s best to avoid letting the soil dry out completely.

Temperature and Humidity:

Hibiscus mutabilis ‘Rubrum’ is hardy in USDA Zones 8-10. It enjoys warm temperatures and can tolerate mild frost, though it may die back in winter, regrowing from the roots in the spring. In colder climates, consider protecting it with mulch.

Fertilizing:

Feed with a balanced, slow-release fertilizer in spring as new growth begins, and continue monthly throughout the growing season. A fertilizer high in phosphorus can promote more abundant blooms.

Pruning:

Prune in late winter or early spring to remove dead or damaged wood and to shape the plant. Regular pruning helps maintain its form and encourages more vigorous growth and flowering.

Mulching:

Mulch around the base of the plant to retain moisture, regulate soil temperature, and suppress weeds. Apply a 2-3 inch layer of organic mulch, keeping it away from the trunk to avoid rot.

Pests and Diseases:

Generally resistant to pests, but watch for aphids, whiteflies, or spider mites. Treat infestations early with insecticidal soap or neem oil. The plant is also relatively disease-resistant but ensure good air circulation to avoid fungal issues.