Nancy's column for August 20, 2005
Hot Weather Is Perfect For Growing Heat-Loving Basil
This long, hot summer may be turning you into a limp rag, but it is the perfect weather for growing great-tasting basil. This Mediterranean heat lover thrives in hot, dry weather, and this year I expect a bumper crop.
Basil grows best in moderately fertile soil that drains well. In her book, "The Bountiful Container" (Workman $16.95), herb-authority Rose Marie Nichols McGee, says that over-watering and over-fertilizing basil ruins its flavor. "Let the soil dry a bit between waterings," says McGee. She recommends fertilizing when transplanting and again sometime in midsummer.
Another secret to growing a season-long supply of great-tasting basil is pruning and continual harvesting. This stimulates the plant to grow and produce more leaves.
To encourage branching, begin by pinching off the tip of the plant as soon as it produces its second or third set of true leaves. The next round of pruning starts when these side branches produce three to four sets of leaves. Cut back these branches just above the oldest set of leaves. Within three weeks or so, the plant will produce two branches from each previously pruned branch and the basil will be ready for another haircut. If kept pruned, it will increase in size and continue to produce new leaves until frost. When pruning, be sure to leave at least 1/3 of the leaves on the plant so it has enough resources to feed itself. By staggering the pruning of the plant by a week or so you will also insure a supply of basil.
Pick basil in the morning after the dew has dried the leaves. This is when the essential oils are the strongest.
The flavor of basil diminishes when it flowers, so cut off the buds as soon as they begin to form. Taking them off a set or two of leaves below where the buds are forming will slow the production of new ones. If you just pinch out the bud, a new one will quickly reform.
Basil is very sensitive to cold and some say its delicate oil begins to evaporate soon after picking, so it's best to use it fresh from the garden. If it has to be stored, keep it in a glass or pitcher of water at room temperature rather than in the refrigerator. Plants stored in a cold fridge may turn black and limp.
In addition to using the basil fresh in salads, and as a garnish for fresh, sliced tomatoes, I store lots of it for use in soups and sauces over the winter.
I dislike the flavor of dried basil, so I prefer to freeze it.
Some books recommend processing the leaves with water in a food processor and freezing the blend in ice cube trays. However, I think olive oil does a better job of not only preserving the flavor, but the color as well.
Purists prefer to use a mortar and pestle to puree the basil because crushing the leaves brings out more of the flavor. But this takes a real time commitment.
Other cooks prefer to freeze the leaves whole by layering them between sheets of wax paper and storing them in a freezer bag. When they strike the frozen leaves on the kitchen counter, before they have a chance to defrost, it shatters them into small bits. Although the leaves will darken, they do retain much of their flavor when frozen this way.
I make up large batches of pesto and freeze it in ice cube trays. When frozen I wrap 3 or 4 cubes in aluminum foil and store the little packages in Ziplock bags in the freezer. This method of wrapping and storing keeps the basil from becoming coated with ice crystals as time passes.