Does Basil Reseed & Grow Each Year?

Temperature

• Basil is native to India and grows year-round in tropical climates. In cooler regions, it usually grows as an annual from May to October. Basil seed germinates in about seven days at temperatures between 65 and 85 degrees Fahrenheit. Optimum temperature is 70 F. Basil plants suffer at temperatures below 40 F and will not survive freezing. Seeds that fall from mature plants may overwinter in the soil and germinate the following spring. Seedlings need light and are extremely sensitive to cold temperatures.

Soil

• Basil grows best in loam or light sandy soil with a pH between 5.5 and 6.5. Plant basil seeds 1/4 inch deep and keep the soil moist but not soggy. When seedlings emerge, water them from the bottom to prevent damping off. If basil reseeds itself and several seeds germinate close together, thin them so the plants are six inches apart. After the seedlings emerge, wait until the first set of true leaves have formed and transplant them to give all the plants enough room to grow.

Save Seed

• To save seed, allow the basil plants to flower. Flower racemes start to mature from the bottom and progress up the stem. Cut the stem when the bottom seed capsules turn brown and dry them in a well-ventilated area away from direct sunlight. Rub the seed pods over a fine wire mesh to remove the seeds. Store fully dried seeds in an airtight container in a cool, dry and dark location such as a freezer.

Planting Saved Seed

• Basil seed remains viable for five years. When you are ready to plant, allow the container to warm to room temperature before you open it to prevent moisture from condensing on the seeds. Expose the seeds to air for a few days so they gradually pick up some moisture before you plant them. Planting saved or bought seed gives you greater control over the growing environment than relying on basil to reseed itself.