Basil does not like temperatures below 45 degrees. Space herbs so each plant gets good air and light to prevent disease and promote good growth Avoid heavy fertilizers on herbs. Aged compost should feed them just fine. Mulch herbs to retain moisture during summer. Sand or gravel is an excellent mulch for gray-leafed herbs that are prone to death from our humidity, says herb grower Billi Parus.
Heat radiating up from the sand and gravel keep the underside and interior of the plant hot and dry.
Borage Pinch, prune and harvest your herbs. For great oils, keep the flowers pinched off. Harvest herbs in the morning, just after the dew is dried, but before the sun gets hot. The concentration of essential oils is highest at this time. For drying herbs, cut them just before the plants bloom.