When Is Basil Ripe to Harvest?

The Use

• Cut the leaves before the plant flowers if you want to use basil for cooking. When basil is used as dried leaves, those leaves are cut as buds appear, but before the appearance of flowers; for essential oils, allow the plant to bloom and harvest during the blooming period, advises Purdue University's Center for New Crops and Plant Products. The leaves lose their pungent flavor, becoming bitter, once the energy of the plant is transferred to the flowers. The flowers then take on a pungent aroma. According to Ohio State University, the leaves must be harvested within three weeks of new growth, but can be harvested weekly in smaller amounts.

The Plant

• Basil plants develop their leaves in pairs. When the first three sets of leaves develop, both OSU and Purdue state to look for two sets of tiny leaves growing underneath the sets at the stem junction. Pinch the top three sets above those smaller leaves. The smaller leaves will become branches and develop leaf sets of their own.

Time of Day

• There are two viewpoints pertaining to what time of day is best to harvest basil. OSU suggests harvesting basil to be dried during a sunny morning before the dew evaporates. Michigan State University Extension recommends basil meant to be stored is best harvested as late as possible in the day. Both MSU and OSU agree to avoid harvesting when the sun is hot during the middle of the day.

Storage

• If you plan to store basil, MSU horticulturalist Diana Dostol produced a study showing that basil stored in perforated plastic bags at room temperature keeps longer than basil kept in refrigeration. The study showed refrigerated basil kept for up to three days while unrefrigerated basil lasted up to 14 days.