Prep to plant lavender
All of our lavenders, with the exception of the spanish lavender, are zone hardy for 5-8. One of the best ways to find out if lavender will grow well in your area is to see if your local greenhouse carries any variety. Place your lavender in the design that makes you happy and allows room for air currents around the plant when they reach maturity. Lavender loves the sun and hates to have its feet wet, so choose a position with good drainage and plenty of sun. They are adept candidates for rock gardens. Humidity can be an issue in the Southeastern and some Midwestern states. Lavender isn't fond of damp, still air which makes the plant more susceptible to root rot and other maladies. This difficulty can be minimized by increasing the spaces between the plants so the air can move around them more easily. Grow lavenders with plants that have similar sunlight and watering needs. Select soil that is well worked, well drained and so loose you can dig it with your hands. Once established in a garden, lavender is a hardy and drought tolerant perennial. Select a variety appropriate to your area, and pay attention the size requirements for your variety. (Some get to 5 feet across!) Lavender likes a slightly alkaline soil so adjust accordingly. Some sand and well rotted manure or compost will get the plant off to a good start.
Carefully knock the plant from its pot, spread the roots, and place the plant in a hole that accommodates the spread roots. Mixing a little bone meal into the soil mix below the roots will slowly release organics that promote both root and leaf growth. Roots should not be placed directly on the meal, but on a mix of soil and meal. If the stems are long enough, give the plant a little shape by pruning, this will start the stems branching. If you keep dogs or there is an abundence roving dogs in the neighborhood bone meal can attract them and they will dig up your plants. We lost over 100 plants the first year because of this. When you water the new transplant for the first time, you can use a liquid fertilizer instead of plain water. A two-inch mulch of sand will moderate the soil temperature and reflect heat and light up to the plant. More heat creates more fragrant blooms.
Caring for lavender in the Spring
Remove the blossoms in the fall. Prune your plant in the early spring to 2/3 its size, leaving a couple of inches of green above the woody stems. It seems drastic but this will stimulate new growth. Don't be afraid to prune them in this way you will thank yourself later. Lavender responds very well to being shaped because plants that are not pruned may have a tendency to fall open in the middle and sprawl esspecially in snowy areas.
Picking lavender flowers
When your lavender has blossomed, the flowers can be picked for many uses. If you desire a fresh bouquet, pick the blossoms when half of the flowers on the blossom head have opened. If you are picking to dry the bundle for crafting or sachet, pick when 3/4 to all of the blossoms are open. If you are producing oil then full bloom is fine on french lavender.
Caring for lavender in the Fall
In early Fall, cut the GREEN of your lavender back so about one or two inches of green remain. This will promote fuller growth for the next season and it will look better throughout the winter. Don't cut into the wood if you can avoid it. It is difficult for the older wood to produce new shoots. It's best for the plant if the pruning tool you use is sharp and clean. We use a sickle and gas powered hedge trimmers but hand shears work also.