Part of the fun of working with the lavender the way we do is that because it’s less of a business and more of a hobby we can sometimes try things that in a more corporate world would have been a bit too risky. Case in point is the 500 or so different Intermedia that were planted last year. The varieties included mostly Grosso and Phenomenal with a smattering of other kinds.
The problem with Intermedia is that it is less hardy than Angustifolia, and given our climate (zone 5) it is a borderline plant to make it through the winter. The plants need to be very well placed away from extreme cold and wind. And although the Phenomenal lavender we initially planted did fairly well, they probably should be covered to be sure of survival. This is information we have gleaned from reading, experience and listening to others in the industry.
With all that said we planted a swathe of Grosso and Phenomenal (and 150 Silver Frost which is even less hardy, recommended for zone 7!) on the main hill with the other lavender. We didn’t cover any of the plants either. To put things mildly things did not turn out well. Out of all the plants only 8 Grosso survived. Not a ringing endorsement of our planting prowess.
Here is the dead Silver Frost –
And some Grosso and Phenomenal rows!
So what happened other than the plants being a borderline zone 5 plant? We think one of the major factors was that our hill faces to the north and is fairly exposed. So the wins whips up the hill in winter making things a fair bit colder than they should be. Also, there was a thaw-freeze in January. Temperatures rose to the point the soil started thawing up a bit and we then went back into a deep freeze. We didn’t think it was an unusually cold winter but could be wrong.
So, what did we learn?
- We should take risks, but small ones. Do it with 50 plants, not 500!
- Intermedia needs to be more sheltered.
- Intermedia may need to be covered.