Most herbs can be planted in the spring after the last frost, with the specific timing varying according to the amount of cold that a particular variety can tolerate. The majority of herbs can be transplanted when nighttime temperatures reach 55 degrees F. Some herbs, such as parsley, can tolerate cool nighttime temperatures while others, such as sweet basil, will not thrive until temperatures are warmer.
Herbs for Early-Spring Planting
The following herbs can be transplanted into the garden in early spring as soon as nighttime temperatures reach 45 degrees F: Chamomile, chervil, chives, lovage and sorrel. These herbs can also be transplanted later in the spring as the establishment of these plants will not be negatively affected by the higher temperatures.
Herbs for Mid-Spring Planting
The following herbs can be transplanted into the garden in mid-spring, as soon as nighttime temperatures reach 55 degrees F: Anise hyssop, borage, catnip, coriander, dill, fennel, feverfew, lemon balm, oregano, parsley, sage, savory, thyme and wormwood.
Herbs for Late-Spring Planting
Sweet basil does not tolerate cool temperatures. It is recommended that plants be transplanted outdoors in late spring or early summer when nighttime temperatures reach 65 degrees F.
Herbs for Early-Summer Planting
All of the herbs mentioned above can be successfully transplanted into the garden in the first weeks of summer.
Herbs for Mid- to Late-Summer Planting
Once the weather gets hot there are some herbs that will not do well. These include coriander, chervil and parsley. Sweet basil, on the other hand, can be planted well into mid-summer. When transplanting seedlings in the summer, care must be taken to avoid shock by shading the plants for a few days after transplanting.