Harvesting basil is simple and should be done often to ensure a healthy plant. If this does not happen, the plant will not produce as it should and it may start to flower, which can alter the taste of the leaves for the worse. By harvesting basil often, you can be sure that your plant will be large, bushy, and be producing great tasting basil all season long. When your plant is full of large, silky leaves, it is probably time to harvest.
When To Harvest
The correct time to first harvest your basil plant can vary from plant to plant, but you can usually figure out when it is time by looking closely at the leaves. After your basil plant is at least a foot tall, check the leaves on the stems. The first thing you should notice with your basil plant is that the leaves grow in sets of two. These two leaves are directly across from each other on the stem. You can start harvesting leaves when there are at least three pairs of leaves, but it is recommended to wait until there are at least four to six pairs of leaves on a stem.
Pruning
Holy basil flower
If the plant is not pruned often, flowers may begin to form at the top of stems. These flowers are usually one to four inches long, first starting off small and green. As they grow larger, small flowers will appear. When you first notice a flower forming, it is best to pinch it off right away. Flowers can alter the taste of the plant and keep it from growing.
Harvesting basil stems (Source)
When harvesting the plant, you have the option of harvesting by cutting parts of the stem or by picking individual leaves. Either way will encourage new pairs of basil leaves to grow, which in turn will be picked, and then encourage another pair of leaves to grow.
If you are harvesting by cutting part of the stem, find the bottom two pairs of leaves, and make a cut above that point on the stem. The plant will keep producing new leaves and branches on the stem if you make the cut above the bottom two pairs of leaves.
Another way to harvest the plant is to pick, or pinch off, individual leaves. This is done by simply grabbing a leaf, and pinching it off from the stem. When you use this method, a new set of leaves will grow back in. This method of picking basil is ideal for those who want to cook with fresh basil whenever it is needed.
By pruning or harvesting your basil plant often, at least once every two to three weeks, you will be sure to have a plant that is thick and healthy, while producing lots of beautiful, silky, green leaves all season long. As long as you keep pruning away, production will continue all the way until first frost. If you must harvest more basil than is needed at the time, then you can simply freeze or dry the basil for future use all year long.