Growing lavender has been one of the most difficult things to grow here because of the heavy soil and cold constant wind in the winter. The variety of lavender that has been the most successful is Lavandin Lavandula x intermedia ‘Grosso,’ a French cultivar that has proven for us to be hardier than the more common English varieties, but yet does last more than two or three years. All English varieties such as ‘Munstead’ and ‘Hidecote’ have failed. ‘Grosso’ is larger and considerably more fragrant and is the primary type used for commercial lavender production.
Full sun and good drainage are essential for lavender to thrive. The lighter and more alkaline the soil, the better. Once established it will require very little watering and fertilizing. You will need a good pair of sharp pruners as pruning and timing or it are vital to good flower production. In bloom, it will produce a 3+ foot mound.
Location
— site in eight hours or more of direct sunlight
— area should be dry where water does not regularly pool with good to sharp drainage
— a spot with the least amount of winter wind is ideal
— allow two feet around and above the current size of the bush for flower wand growth
Process
— dig a hole at least 12″ wide and deep; though 18″ would be better if soil is heavy clay
— mix the excavated soil with an equal portion of a purchased sandy topsoil (be sure the top soil is loose and sandy)
— refill the hole slightly so that the plant can be positioned the same depth it was previously growing
— set the plant in the hole and water in with half-strength Miracle-Gro
— backfill and tamp
— water (not with Miracle-Gro solution) to set the soil
Mulch
Lavender does not like to be mulched because it doesn’t want to be moist. However, you will want to use a light-colored gravel or crushed stone in lieu of mulch. The idea is to reflect light up into the plant to keep it from getting woody.
Fall Care
Keep air circulation flowing around the plant by ensuring hat dead leaves and debris are continually removed from the base of the plant.
Winter Care
It is vital to ensure that dead leaves and debris are continually removed from the base of the plant and that airflow remains unrestricted, otherwise the woody stems and crown may rot. However, snow cover is ideal as it will insulate and protect from drying wind and winter sun scorch. Through winter the lavender will maintain its foliage, but as spring approaches it will begin to wane and may even look dead.
Spring Care
On or about April 1 you will want to do your spring pruning. I did a severe late-summer pruning to rejuvenate this plant so it may not need a spring this time around. When doing the spring pruning in general you want to remove 2/3 of the green/gray soft growth. Don’t cut back into the wood as new growth is difficult to get started there. The idea is to keep the woody core of the plant to a minimum by forcing new growth to begin as far back into the plant as possible. As you pruning, keep to a mound shape. Lavender will continue to look bedraggled until the weather warms. A light watering of Miracle-Gro Flower booster after pruning will help.
Summer Care
Flower wands will begin to show in late May and will be in bloom by late June, lasting until the beginning of August. No care is needed except to water sparingly the first year.
Drying: the best time to harvest for drying is when a 1/3 of the bloom is open, usually around the first or second week in July. This will give you premium-quality lavender for dried flower arranging when you need the stem intact. Cut the stems where they emerge from the foliage. Bunch the stems together, keeping stem bunch about 1″ or less in diameter. Fasten with a rubber band and hang upside down in a cool dry place for several weeks. You may get a small rebloom later in the season, but doesn’t always happen.
Summer pruning: when the flowers have faded (dried on the plant) around the first week in August, cut off all stems where they emerge from the foliage. These stems can also be bunched and dried and used to make sachets or cast in a fire for a fragrant delight. As with spring pruning, cut back 2/3 of the new growth that occurred during the summer.
