I like to have a steady supply of herbs in my terracotta garden as long as possible. To achieve this without constant reseeding or succession planting, I harvest the tops of my herbs throughout the summer and fall season. The herbs should continue to grow as long as they are not allowed to flower.
The key to this is to monitor your herb garden daily, if not twice a day, for any sign of budding. Those that I’ve found to bloom (or bolt) quicker than others are Dill, Basil, Cilantro and Summer Savory. I highly recommend that you keep a close eye on those this growing season. In fact, these are the herbs I would monitor twice daily after they get above 6 inches in height.
Personally, my Sage, Thyme, and Oregano did not begin to bud until the end of early fall. Thus, I did not have to worry much about harvesting anything from those aside from what I needed for a meal any given day. This timing couldn’t be more perfect.
For my last and final herb harvest, I wait until the weather cools and the danger of frost looms. At that time, my husband and I will go down the line of terracotta pots with scissors and enough bags in hand for each individual herb. We cut each perennial approximately 2-3 inches from the ground, careful to still keep a few leaves on each sprig or stock in the pot. The annuals we cut flush with the bottom.
After depositing the herbs in their individual bags in our kitchen, we move all the terracotta pots into the greenhouse with the perennials under drip spouts. This way the herbs will get water all winter long whenever the yard hydrant that particular hose is connected to, is turned on. This way, when you check your perennial herbs in the spring, you should have some fresh green sprouts to welcome you.
I mentioned in my prior herb post, the reason I chose terracotta pots was to ultimately be able to bring them in our house during the winter. Since we are currently not in our own home, they go to the greenhouse as mentioned above. When our own house is finished, they will come indoors. If this is the method you employ, just continue the cycle of summer harvesting through the winter! Fresh herbs all year long!