Cultivation
of Costmary
Site: Costmary grows best in full sun and
a light, dry but fertile soil. It's a perennial
that can grow up to almost 3 foot and it spreads
similar to mint. If you can manage to give it a
sunny corner in your garden it will be happy, and
one plant will be plenty. Many gardeners complain
it's invasive, which it can be. If you deadhead
the blooms before they go to seed and pull up any
roots that spread, it can be kept under control.
I do this with my mint too, and as long as I stick
to the maintenance it's fine.
Propagation:
Costmary is hardy to Zone 4 and is propagated by
root division. The seed is not readily available,
so it's best to buy a plant.
Growing:
You can grow it in shade, but it will become leggy
and won't bloom. I've seen quite a few resources
labeling it a shade herb, but it really won't do
its best in a shady location. It can be cut back
to keep it from getting to full or tall.
Harvesting:
The young tender leaves can be gathered and
used fresh at any time during the season, but for
winter use they should be harvested when the plants
begin to flower, and should be dried rapidly in
a well-ventilated, darkened room. If the leaves
are at all dusty or gritty, they should be washed
in cold water and thoroughly drained before drying.
Culinary
Uses: Usually used for medicinal purposes, but
can be used as a flavoring in soups (especially
carrot soup), stews, and salads. Use only in small
amounts as it has a sharp tang. Use it to clear,
preserve and flavor beer.