Mark Anderson wrote:

I think I did something stupid. A couple of weeks ago the weathermen
forecast night time temps in the 20s here in Chicago, Zone 5. I panicked
and brought in all the house plants. I also brought in my Rosemary bush
which is 1 1/2 years old, which I nurtured inside all last winter under
fluorescents. I placed the bush under fluorescents and for some reason
it just started dying. There is some green in the leaves but it doesn't
look good, a lot of stems have completely died. The root system is big
and it grew in a 24" wide container. I really hoped I could overwinter
it inside and have it get huge for next summer. Now it looks hopeless.

Does anyone have any idea as to how to save this? I can't believe the
root system would just die off like that. If I cut the entire plant down
will the roots spawn new stems? I since moved the plant from
fluorescents and placed it under my new HID High Pressure Sodium lights
for my indoor winter garden. It gets 14 hours of "sunlight" now.

The problem is, of course, trying to grow a shrub (not merely a
perennial or annual) outside of its proper climate. You must
expend a great effort and still expect some grief.

In its natural environment, rosemary has a dry summer and a
not-so-dry winter (some rain but not much). The soil is "lean" but
not totally devoid of nutrients. The plant grows in full sun.

I have a rosemary bush in front of my house. It's more than 25
years old and is taller than I am (until I prune it). In the
summer, it gets watered perhaps 3-4 times. In the winter, I let
the rain take care of all watering. I never feed it.

It flowers in the early spring, after which I prune it for
appearance and not for renewal. Most of the pruning is to expose
the gnarled branches that are so picturesque.

Yes, we do get frost in the winter, sometimes several consecutive
nights. But it all disappears with sunrise. We have had snow
twice since I planted the rosemary; the snow never lingered more
than a few hours.

In the same bed as the rosemary, I have dwarf coyote bush
(Baccharis pilularis) and a valley white oak (Quercus lobata).
They all take the same ca rarely watered and never fed.
However, since they are near line of rose bushes, I would not be
surprised if their roots extend under the roses to capture some
water and nutrients or even farther under my neighbor's front
lawn.

--
David E. Ross
Climate: California Mediterranean
Sunset Zone: 21 -- interior Santa Monica Mountains with some ocean
influence (USDA 10a, very close to Sunset Zone 19)
Gardening pages at http://www.rossde.com/garden/