1. Excellent Drainage
2. Full Sun
3. Grow from Plants and/or Softwood Cuttings [Not from Seeds]
Soil, Planting, and Care
‘Set out plants 12 to 18 inches apart in an open area with full sun and good air circulation. Plant lavender in well-drained, slightly alkaline soil with a pH between 6.7 and 7.3. You can add builder’s sand to the soil before planting to increase drainage, which is vital because lavender will not tolerate excessive soil moisture or humidity. To further improve drainage, plant lavender in a raised bed, along a wall, or near the top of a slope. In an herb or perennial bed, ensure good drainage by planting lavender on a small mound. Lavender flowers bloom in summer; you can clip faded blooms to encourage continued blooming throughout the warm season. Prune lightly to promote branching, especially in spring once the plants show new growth.
“Sprinkle bone meal or other phosphorus-rich fertilizer around each plant in the fall to make it stronger and more winter hardy. Work the fertilizer into the first inch of soil, or let the rain soak it in.’
Consider starting the plant as a potted plant.
“Remember that lavender needs good drainage and good air circulation. Do not over-water, and allow the soil to dry before watering again. When there is a lot of heat and humidity, fungus can attack the plants, turning the leaves brown. To minimize the chance of having such a problem, mulch with pebbles or sprinkle sand around the base of the plant for faster evaporation. If you cut the blooms, trim in a way that thins the plant a bit, leaving it open for better air circulation.
Harvest and Storage
“Harvest lavender stems at any time by cutting them from the plant. However, avoid clipping more than every third stem to keep the plant looking full. Flowers will keep their perfume for months when you harvest just before they are entirely open. To dry flowers, gather a bunch of stems and hang them upside-down in a dark, well-ventilated place to preserve color and keep the stems from molding.” http://bonnieplants.com/growing/growing-lavender/
Mustead and Hidcote Lavender are two especially hardy varieties.
Best Lavender Varieties for New Jersey Gardens
“The English lavenders (Lavandula angustifolia) are earlier season bloomers, starting in mid-to-late spring and finishing in early summer. Examples of English lavenders include ‘Munstead,’ ‘Hidcote,’ ‘Hidcote Pink,’ ‘Jean Davis,’ ‘Sarah’ and Lavandula vera (literally, “true lavender”). Many of these lavenders maintain a compact growth habit and have a tremendous fragrance. English lavenders are hardier than the non-English types, but as with most lavender, they do not tolerate poor drainage or high humidity. ‘Munstead’ is probably the most heat tolerant of the English lavenders.
“The English lavender hybrids, known as lavandins, bloom from early to mid-summer. Lavandins (Lavandula x intermedia) are a cross between Lavandula angustifolia and Lavandula latifolia, an evergreen shrub of the Iberian pennisula. Examples of lavandins include ‘Abriali,’ ‘Fred Boutin,’ ‘Grosso,’ ‘Hidcote Giant,’ ‘Provence’ and ‘Seal.’ Lavandins have much larger leaves, greater size and grow faster than the English lavender. ‘Grosso’ is grown for its oil and used in the cosmetic industry. ‘Seal’ is very fragrant and is an all-time favorite for crafts or hedges.
Planting and care
“There are several factors to consider before planting lavenders. The most important is drainage. Do not plant in soggy areas. If the soil is compacted or less than ideal, the addition of organic matter, like compost or peat moss, will help create more air space. Soil pH should be between 6.5 and 7.0, and some acid soil sites may need lime. Clear the area of weeds since small lavender plants cannot compete with aggressive weeds. Make sure that the plants are in a full-sun location; otherwise, they may be smaller and bloom poorly.
Time to Plant Lavender in New Jersey
“The best time to plant lavender is in the spring, after the last frost. It is important that the plant has time to become established before the onset of winter.”
“Avoid major pruning in late summer and early fall in order to limit the amount of new growth damaged by freezing temperatures.”
“Some lavenders can be grown in USDA Hardiness Zones 5 and above however, Lavender grown in well-drained soils can withstand colder winters. Lavender does best in a low humidity climates, and if grown in areas of high humidity it is far more prone to fungal diseases. If grown in a more humid environment, plant spacing should be increased.
“Excellent drainage and full sun is crucial to the survival of lavender plantings no matter what climate lavender is cultivated.
“Most lavender in the world is grown on stony, calcareous soils with a pH range of 6 to 8. Lavender does not grow well in clay soils, or in saturated soils. particularly during the late fall, winter, and early spring, when the plants are dormant. If soil saturation is in question it is recommend that the lavender be planted on mounds or berms. Lavender can be a long-lived perennial, with a typical productive life of about 10 years, although plants have been known to live for 20 years.
“Propagating: Lavender is best propagated from softwood cuttings of standard types. Cuttings results in new plants that are clones of the parent plant, thus guaranteeing that new plants maintain the true properties. Seed may not maintain true to type, and lavender seed is sterile. Lavender is commonly planted in rows or hedges, plants grown from seed will have significant variability in color and plant size, thus creating an uneven and unattractive lavender. Lavender grown for oil, or dried stems, should never be grown from seed. It should also be noted that some lavender varieties are harder to propagate than others. Cuttings should be 2 ½ to 3 inches in length. The leaves from the bottom inch of the cutting should be removed. Dip the base of the cutting in a rooting hormone and place into a sterile planting soil. Rooting typically takes three to five weeks and there should be about a 90% survival rate.
“Another method for propagating lavender is by layering. In the spring, select an outside branch and bend it down to the ground. Measure 8 to 12 inches from the growing tip. Remove all leaves and foliage from this section of the branch, leaving about 6 inches of foliage at the end of the branch. Dig a 3 to 4 inch deep hole, moisten the area of the branch that has been defoliated, and sprinkle with a rooting hormone. Pin the branch down in the ground, and then cover the branch with soil, leaving the end with foliage exposed. Keep the branch watered and once it has rooted, cut it off from the parent plant and replant. …
“Planting: Before transplanting it is best to let the plants adapt to the environment by placing them by the fields to be planted, for several days prior to transplanting, keeping them moist and in full sun. In mild climates for instance below Zone 6 fall is the preferred time to transplant lavender. Plants planted in the fall will have more established root systems and be better able to thrive hot, dry summer days.
In the higher Zones, spring planting is best.
Plant spacing is important to consider when laying out the fields. Spacing the plants has a great deal to do with the end product you intend for the lavender. Growing lavender for oil production, plants can be spaced closer than if your intent is to cut the lavender by hand and create dried lavender bundles. Spacing rows less than 6 feet apart makes hand harvesting and other work difficult as the plants reach maturity. Spacing plants within rows closer than 3 feet apart also makes hand harvesting more difficult, as the plants grow, the stems from adjacent plants become intertwine and make it difficult to grasp the stems, for cutting the bunches.
Typically, lavender should be planted on 3 foot centers with the rows on six foot centers. This allows for mowing between the rows verses extensive weeding. However, some growers like to plant relatively densely within rows. Denser plantings produce larger harvests in the first year or two, and planting more densely helps limit the plants mature size, which reduces the likelihood of older plants breaking apart in the middle. Spacing of 5 feet between rows and 30 inches between plants results in approximately 3,400 plants per acre, and a spacing of 6 feet and 36 inches results in approximately 2,400 plants per acre.
“Before planting, it the ground should be properly prepared. Weed should control should be established, and the field tilled to a depth of at least 10 inches. Any soil additives such as lime should be applied prior to planting. …
“Pruning: Pruning is essential for the health and production of lavender plants. It should begin with newly planted plants by removing the flower stems for the first year. This will improve plant vigor and allow the plant to develop better foliage and root system. Lavender that is not pruned, will break open in the middle, becoming woody, ugly, and unproductive. Pruning of the flowering stalks and upper growth points stimulates development of new flowering buds for the next year’ production.
“Lavender should be pruned aggressively, but it is important not to prune back into old wood, as this may hinder the reproduction of new shoots, and a lavender plant can sometimes be killed by over pruning into the old wood. The old wood is gray to black in coloration. It is best is to leave a couple of the current season’ wood growth. Pruning should be done in the fall and in areas with harsh winters it is best to prune in the early fall before the first hard frosts. Hand shears can be used for pruning or for larger farms, gas powered hedge trimmers may be utilized.”
“Harvesting for Quality. Lavender must be dry when harvested. Harvesting when wet can cause discoloration, mold in bundled lavender, and can potentially result in chemical changes in the essential oil that can reduce quality. It is also ideal not to harvest when it is very hot, which may cause wilting and oil reduction. The best time for harvest is from mid-morning until early afternoon.
“Yields: The harvest of dried lavender buds and bundles will vary depending on the variety, however on the average, mature plants should yield between 4 and 6 bundles per plant (bundles averaging about 150 stems per bundle).
“Drying: Lavender should be dried as soon as possible after harvest, as this insures the highest quality and color. Lavender is typically dried in small bundles hung upside down in a dark, well-ventilated area. The lavender is gathered in small bundles held together with a rubber band. The rubber band keeps the bundle tight as it provides the elasticity needed as the bundles shrink during the drying process. The lavender bundles are usually hung using a paper clip with one end bent to hang with and the other end hooked through the rubber band of the bundle. The bundles are hung in a variety of methods, some are hung on wire or individual hooks. Whichever method of hanging is utilized for the lavender bundles, it is important to insure enough space is provided between bundles to allow good air flow. Low humidity is also important in the drying process as high humidity can cause lavender to mold. If the dried lavender is intended to be used for loose lavender buds, then the lavender buds should be stripped as soon as possible after it is dry, and the buds placed in sealed containers.”