After going over my notes and completing the harvesting of the last of our varieties (Buena Vista) I thought now would be a good time to go over pruning lavender again.
Lavenders that are not kept well pruned will become very woody and spread over time. They will fall open and show a wide-open space in the middle with long woody stems. Not very visually pleasing. Sometimes you can severely trim back these plants in the spring so that new growth is forced from the bottom. Depending on how old the plant is, it may or may not work.
The key to pruning is to start when the plant is young and still in the pot. Pinch the new growth in order to encourage lateral branch formation and even cut off the flower buds in the first year to ensure a larger plant and abundant spikes for the following season (this is a primary consideration if you are a commercial grower).
REMEMBER: The last cutting on sage, lavender, or oregano should be made late August or early September.