Growing new lavender plants from mature specimen cuttings isn't difficult, and it's an economical way to increase your stock. Here's how Andrea McFadden of Okanagan Lavender Herb Farm does it—and she should know: she propagates between 1,200 and 1,500 plants every year between April and June.
You will need
- a mix of equal parts peat moss, clean, weed-free sand and perlite or vermiculite
- peat or plastic pots, or plastic or wooden trays. Make sure containers have drainage holes
- a healthy, mature lavender plant
- pruning shears
- rooting hormone for semi-woody plants with a fungicide to help prevent damping-off (a soil-borne fungus that attacks seedlings or cuttings at the soil line, constricting the stems)
Have everything set up before taking cuttings so they don't dry out.
1. Fill containers with damp soil mix; gently tap bottom on table to eliminate air pockets. Lightly water and tap again.
2. From mature plant, select a branch with smaller branches growing from it and cut off from parent plant
3. Gently grasp one of the side branches of the cut branch between your thumb and forefinger. Carefully and slowly peel down from branch, allowing a “tail” or “leg” to remain on the cutting you're pulling off. (Discard main branch.) McFadden recommends using pieces 10 to 12 centimetres long, leaving five to seven centimetres extending above top of pot. Cut to size, if necessary.
4. Using your fingernail, carefully scrape a bit of the outer layer, just above leg at base of cutting.
5. Remove any leaves on bottom half of cutting. Dip bottom of cutting in rooting hormone.
6. Make a hole in the soil using a skewer or chopstick. Carefully push cutting a little more than halfway into potting mixture. Make sure no leaves touch the soil. Gently firm soil around the base of the cutting. If using large pots or trays, space them five centimetres apart.
7. Place cuttings in bright light and mist daily; don't let them dry out. McFadden recommends leaving them uncovered, as lavender won't tolerate a build-up of moisture inside an enclosure.
In about two weeks, look for a couple of pale green new leaves; this indicates root growth. Move cuttings outdoors to an area where they'll get a bit of morning sun but shade the rest of the day. In about eight weeks, they can be transplanted into the garden. Remove any flower stems that emerge from cuttings to direct plants' energies into making new roots.
Don't be discouraged if some of the cuttings fail to root. A 50 per cent success rate is normal, according to McFadden.
Top photo: 'Royal Velvet' English lavender