Water Rubia agostinhoi moderately during the growing season, allowing the soil to dry slightly between waterings. Reduce watering significantly in winter to prevent root rot.

Ensure good drainage to avoid waterlogged conditions, which this species dislikes.

Prune Rubia agostinhoi lightly after flowering to maintain its shape and encourage bushier growth. Remove any dead or damaged stems at any time. Avoid heavy pruning, as it can stress the plant and hinder future blooms.

Propagate Rubia agostinhoi from semi-hardwood cuttings taken in summer. Root the cuttings in a well-draining potting mix in a warm environment.

Alternatively, sow seeds in spring under glass, but germination can be slow and erratic.

Repot Rubia agostinhoi every 2-3 years in spring, or when root-bound. Use a well-draining potting compost. Choose a pot only slightly larger than the previous one to avoid excess moisture retention.

Handle roots gently during repotting.