Arboretum & Botanical Garden Bulletin Board
Plant of the Month
Location: Grid O18 West side gravel road, up the slope from the Peek bench (the bench with a keystone block retaining wall).
The Coastal Redwood really has no business surviving in Moscow, Idaho, but surprisingly we have two living in the Arboretum. The older of the two was planted in 2019. Coastal Redwoods are native from Northern California north into Oregon in a narrow band between the ocean and the summits of the Coast Range mountains. The climate of that area is mild with lots of precipitation and very frequent fog.
Some references say the Coastal Redwood is zone 7 (0-5° F), and others list it as zone 8 (10-15° F), but either of those are reserved from the -22°F it survived in the Arboretum last winter. It did freeze back most of the top growth last year, but it re-sprouted and grew quite a bit last summer.
It is probably still too soon to tell, but for now I did not see any obvious damage from the severe cold we had last week.
Winter finally decided to make an appearance in Moscow last week, although our version was still mild compared to lots of other places. The lowest ‘official’ low temperature I saw was -16° F, certainly cold enough to damage some of the less hardy things we are trying to grow. The good news is that we also got about 6 inches or so of snow before the cold showed up, so at least some plant crowns and such at ground level did have some insulation. Undoubtedly there will be some damage, and undoubtedly there will be surprises both ways — what was damaged and what was not.
Even after a fairly dramatic warm up, and three days of rain, not a lot of the snow has melted, and unfortunately, the upper pond still has not filled up after dropping to record low levels last summer.
- No current events
When visiting the Arboretum, please remember that for your safety, the safety of others and for the protection of wildlife and plant collections, no pets are allowed. Ice on ponds is very unstable—stay off the ice.