Between mid-June and mid-July, the landscape of Southern France comes alive with the color of deep purple. Lavender grows everywhere — along the edges of streets, highways and traffic circles, in great earthenware pots on sunny terraces, and most conspicuously in vast commercial gardens sprinkled liberally among the sun-baked hills stretching from Avignon to Nice. As the French say--c’est partout — it’s everywhere.

Visit Provence during the summer and the memory of row after row of puffy lavender spikes shimmering in the sun lingers long after you’ve left France. You’ll find yourself searching through your pockets for fragrant remnants of flowers you picked along the roadside.

Centuries before lavender became a commercial crop in Provence it grew wild throughout the countryside stretching from the Rhone River Valley to the Mediterranean Sea. The hot dry climate of Provence brings out the best in this delightfully aromatic plant.  In Fort Collins we are blessed with these same growing conditions.

The fun you’ll have with lavender begins when you choose the varieties to showcase in your garden.  Lavandula angustifolia (English) and Lavandula x intermedia (Provencal) do well in our climate and are hardy perennials to zone 5.   Angustifolia is the purebred classic—early flowering, robust, excellent as a culinary herb.  Intermedia, also known as lavandin, is a vigorous intensely aromatic hybrid cultivated mainly for its oil and prolific flowers.

Among the L. angustifolia family members, choose “Munstead” for its heat and cold tolerance and lighter colored flowers.  (see photo at left)  If deep purple is your passion, “Hidcote” is a good choice although it’s a bit more finicky in intense heat. The diminutive “Nana”will grow only to about 10” high making it the perfect choice for a rock garden.  “Provence” and “Grosso”, two hardy lavandins, thrive in heat—the hotter, the better—and reach a height of 30 inches to produce the showiest blooms.

Before planting it is essential to prepare your beds to provide optimum growing conditions. Lavenders require very good drainage and at least six hours of sun daily.   They flourish in a sheltered southeast, south, or southwest location. If you are cursed with heavy clay soil (aren’t we all?) work the ground by roto-tilling or hand-digging to a depth of about twelve inches and then amend it with coarse compost to help break up the clay and improve drainage and aeration. A good rule of thumb is to incorporate about an inch of compost into your beds. Bare in mind that lavender does not require extra nutrients, so fertilizer is rarely necessary. Pea gravel (3/8” in diameter) is a good choice for mulch around the crowns of the plants.

Don’t be disappointed if you have no blooms during the first season of growth.   You will be rewarded the second year with an abundance of flower spikes. The English and Provence varieties are perfect low-maintenance candidates for the xeriscape garden and will bask for days in the heat of the sun before needing water. In the spring, trim back the old growth (about 1/3 of the plant) to encourage vigorous new shoots. If your garden is in an exposed location, mulch the plants over the winter to shield them from severe cold.   Be sure to clear the mulch away in the spring when you prune. The best time to harvest lavender for drying is early morning before the sun has evaporated the essential oils. Wait until the moment when the flowers are just starting to bloom and the color of the spikes is intense.  Tie the stems in bunches or spread them out on a screen to dry.   Although lavender is best known for the intense perfume it lends to potpourri mixtures.

L. angustifolia is also a culinary herb.  Use the dried flower buds sparingly in Herbes de Provence mixtures and desserts.   Ice cream flavored with lavender and honey is a special treat.  L x intermedia or lavandin is too intense for culinary applications but wonderful in dried arrangements where the richness of the perfume counts.

Lavender is a striking addition to the garden, especially when displayed in groups.     If you want to make a lasting impression on your friends and neighbors, fill an entire bed with “Hidcote” or “Munstead” or design a lavish border of “Grosso” along the length of your driveway. A more subtle approach is to scatter multiples of three or five throughout a colorful perennial display.  And don’t forget the dwarf varieties. “Nana” is perfect as a low border along the edge of your herb garden. The possibilities are limited only by your imagination and the amount of space you have in your garden.
 

Q:  My cottonwood tree has ants crawling all over it.  What is going on?

A:  The ants have developed a relationship with aphids, insects that feed on the new growth of your cottonwood tree.  By looking at the ends of the branches, you will notice a green insect. The aphids are sucking the sweet juices out of the leaves.  The ants protect these aphids from predators because they are attracted to the sweet secretions they leave behind. To help control the aphids, exclude the ants from the trees by using sprays, sticky bands etc. This will allow the natural predators to keep the aphids under control.

Q: The leaves on my maple tree are brown and look dead.  Is this a disease?

A:  More than likely your maple tree is suffering from leaf scorch caused by drought stress. Don't be surprised if your tree also starts loosing its leaves early. Keep your trees well watered by using a deep-root irrigator or soaker hose put around the drip line of the tree. To help retain the moisture, apply about 3 to 4 inches of organic mulch around the tree but pull the mulch about 6 inches away from the trunk to avoid fungal infections. For further information on properly watering trees during a drought, visit the Save our Shade website at www.watersaver.org

If you are putting in a new landscape, consider subsurface irrigation for your turf grass areas. Since we live in a semi-arid climate the amount you could save on your water bill could quickly outweigh the cost of installing a subsurface watering system. The water is never exposed to surface evaporation and directly waters the root zone. This could result in greater plant health, reduced weeds and a significant water savings.

Is your arugula peppered in "shot holes?" Losing your New Mexican evening primrose to a nibbler? The culprit could be one or several kinds of flea beetles. The chemical carbaryl (Sevin) and permethrin can provide fairly good control as well as diatomaceous earth applied as a dry powder, horticultural oils and some neem products. Pay particular attention to use only pesticides properly registered for use on the crop and carefully read and follow all label directions when applying pesticides.  Row covers, decoy crops and repeated physical disturbance also help!

With all of the early wet weather in the spring, field grasses grew quite tall. This created a huge fire-fuel-potential in open lands and in the foothills. Monitor this link in the fire chain, keep grasses mowed and maintain a defensible fire zone surrounding your home!

The authors have received training through Colorado State University Cooperative Extension's Master Gardener program and is a Master Gardener volunteer for Larimer County.

Gardening and Insect Fact Sheets are available on-line by clicking HERE.

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This page updated:  August 18, 2003