Seagrapes are rarely bothered by pests, and only occasionally fall prey to the seagrape borer, a native moth that eats twigs and branches.
Light
Seagrape needs lots of tropical sun, although the plant is moderately shade-tolerant.
Soil
Sandy soil is best, but it tolerates a wide range of soil conditions.
Water
The sea grape is drought-tolerant, but should be watered if grown in a container; once transferred to the ground, watering is not necessary as long as you live in a tropical area with lots of rainfall, but regular watering can help it grow fuller.
Temperature and Humidity
Seagrape needs warm temperatures; it is not frost-tolerant, and temperatures below 32 degrees Fahrenheit will injure, if not kill them.
Fertilizer
Seagrape can be fertilized with a complete fertilizer like 8-8-8 if planted in soil with low nutrient levels, but will otherwise thrive without regular fertilization.
Types of Seagrape
‘Grandleaf seagrape’ (C. pubescens): This variety looks similar in appearance but is much larger, with terminal spikes of flowers over 2 feet high.‘Pigeonplum’ (C. diversifolia): A common seaside plant, its leaves are a darker green, and it grows taller than the seagrape.
Pruning
Seagrape responds well to pruning and should be pared back in late summer to maintain the ideal shape; when left unchecked, it tends to sprawl. Watering it regularly ensures that it reaches its full potential. Seagrape should be kept in warm, tropical conditions that mirror its natural habitat. This tough and tolerant shrub can be a great ornamental plant for those along the tropical coastline.
Propagating Seagrape
The sea grape propagates easily by seeds or cuttings. To propagate by cuttings, sever a branch at the beginning of spring and replant as soon as possible in a combination of peat moss, potting mix, and sand. Make sure to keep the cutting moist and in a sunny area, with good drainage. The seedlings can grow in a container until they become large enough to transfer into the ground.
How to Grow Seagrape From Seed
Seagrapes grow quickly from seeds, which come from their ripe purplish-black fruit. Seeds must be fully cleaned of any fruit residue, which can cause them to mildew and rot. Once seeds are dry, sow in individual pots in a 50/50 mixture of sand and compost. Water lightly, and cover with plastic wrap. Keep in a warm place, with southern exposure. Seeds should germinate in about three weeks, maybe longer. Once seedlings are 6 inches tall, they can be planted outdoors.
Potting and Repotting Seagrape
Seagrape can be cultivated in a pot and then transferred to the ground. Repotting is only necessary if the roots are protruding from the pot and the plant is still very young. Transfer to a larger container, preferably a plastic one.
Overwintering
Keep seagrapes in full sun in the winter; they may not grow as fast, and may drop leaves, but will recover when the temperature increases.
