How to Grow Sweet Basil in the Tropics
I am fortunate enough to grow Basil at home as it is an easy herb to grow in sub tropics to tropical areas. You should be able to get away with buying seedlings from your local nursery or supermarket once and then never having to buy the plants again.
Plant the seedlings at approximately 30cm (6 inches) apart, preferably in a raised garden bed or large tub. Water them in and fertilize them with Blood and Bone. Don’t let the plants flower by pinching the flowers off when they appear at the centre of new leaf growth.
My Basil plants sometimes have caterpillars eating the leaves. Don’t spray these (as you eat the leaves as well) but simply pull the leaves off that they are on and throw them in the bin. I have not had grass hoppers eating the leaves yet, but I am guessing that because of the strong flavor in the leaves that they are somewhat protected. My pet parrot, which usually eats anything, won’t even touch the leaves.
I also get some black spots on the older leaves, which looks like the leaf dying off rather than scale or mite damage. I don’t worry about this and usually use these leaves as well. You should only see this on older plants and if you fertilize with Blood and Bone you should see dark green, robust growth.
When the plant gets older, it usually goes “yellowy”, has less leaves looks woody or scraggily, let it flower. Do not take any more leaves or stalks of the plant. When the flower heads are brown and dry then cut the flowers off. From here you can either spread these flower heads over the top of another pot and water them or store them for next season. In the tropics we don’t have much of a winter so we spread them over another pot and water them in.
Harvest the leaves by cutting stalks to the desired length or you can pick a few leaves off as you need them to add to your cooking. I usually cut off two stalks that are 30cm (6 inches) long and are covered in leaves with small branches to make Basil Pesto.
With the cut stalks, leave a few leaves at the top of the cutting. Put these cuttings into a jar or container of water, like you would with cut flowers. I leave this on a windowsill where the cut stalks will get some morning sunlight. Replace the water every couple of days and you should get roots forming after a couple of weeks. Stalks may rot at the base and you can cut these parts off. When the roots are at least 2.5cm (1”) long they are ready for planting. Plant these cuttings in your garden as you would with the seedlings (see above) and ensure you water them in and water them daily for the first week. This is the main way that I get more Basil plants to grow in my herb garden.
Hope you enjoy growing Basil!