A colored vine similar to that of cotton, Seagrape is a disease tolerant, drought tolerant, annual vegetable. Seagrape can grow from seeds delivered into enclosed plastic containers and vary in weight to shade the containers. The seed comes with a description of how quickly it will grow if placed in a closed pot in a location with a hot temperature for 15 days.
Though its exact date of establishment is unknown, the prolific Grevillea seagrape was introduced as a wild marigold over a century ago. In recent years it has been artificially cultivated and introduced to the home garden. To call Grevillea seagrape prolific and fast growing and to expect large, petite, colorful plants could be a bit of a stretch. In terms of produce, it is not great.
Growth of individual seedlings is variable, especially if Seagrape is planted in pots indoors. However, if seedlings are sown in a large area with some sunlight, the plants should survive. From our research, Seagrape rates an initial six weeks growth, growing in a relatively small area. As the plant gets established, the area should be increased. But by the time the plants need a portion of their original space, they have already expanded. Seedlings may take from four to five months to produce one dominant, flowering flower. During the first year, the plants may produce only a few stamens or other buds, indicating that the colony had failed to transfer from the soil into the sun. But by year two the plants can bloom abundantly and produce many flower buds on one plant. Growing into a tall crop, they can sometimes reach 8 ½ feet tall, but they also can ripen in a relatively short time of six weeks, their height dropping below five feet by year four or five. Seagrape does not produce nutritious seeds, though they can be mashed for cooking purposes.
Generally, Seagrape prefers moist soil, but that is not as important as good drainage. Some seedlings do die because roots do not expand into the new area or become too abundant. The drought tolerance has been tested over long periods of dry, hot summers and extreme temperatures; plants escaped death in parched conditions but reached their limit during the one long period of tilling and watering.
Early signs of seagrape invasion are weedlike plants at the base of the seeds, such as Lavender Mist, Claw Tomatoes, and the Thorn Brush weeds. Steeplegrass also appears here. Use Trichoderma bacteria to kill these, but I believe most seagrape infestations should be eliminated by using all sorts of mulch, just leaf mulch at the bottom (out of the sunlight) before planting. Keep the mulch moist and dark, but not wet.
Start your Seagrape seedlings in ground that drains well, but the seeds themselves are heavy and require a full wheelbarrow of material to get to the soil surface. The heavy mulch can impede root development, but does provide a dormant zone until the seedlings can be transplanted or transplanted elsewhere. All seeds should be removed from containers during the 1st week in the beginning of the growing season.
Trichoderma bacteria are small viruses which make the Seagrape flowers more brown and less brilliant. However, most of the bacteria escape into the soil and are fairly harmless to plants that are not introduced to it. They can also be treated, by place Trichoderma bacteria on the surface of soil, always before fertilizing. The bacteria are capable of preventing Seagrape from thriving in warmer summer months. But, we used trichoderma bacteria for the first few years to prevent seagrape from spreading.
For this year, Seagrape can be grown from seed. Try to remember that seedlings that are small, hard to remove from the ground, and/or that are growing well on parts of the foundation have the best chance of survival. Seagrape needs lots of soil to grow, and leaves will show up within a few weeks to provide food for soil microbes. Seagrape needs sun and some sun.
Seagrape, and its kin, Seagrape can be grown successfully in almost any gardener’s garden. It needs a diverse soil mixture and consistent well-drained, well-cultivated soil. It is not a long-term friend of poison ivy or anything else that would cause lung or skin irritation, and it does not give off toxins.