Re: Zones
- To: Multiple recipients of list <i*@rt66.com>
- Subject: Re: Zones
- From: B* M* <p*@umich.edu>
- Date: Mon, 29 Dec 1997 10:11:35 -0700 (MST)
Daryl &Kathy Haggstrom wrote:
>
> In reference to Richard Shehorn's question regarding weather zones:
>
> The zones being mentioned are the USDA plant hardiness zones, which are
> commonly found in many seed catalogs (Park's, Burpee, White's etc). They
> are also found in many gardening books. Delaware is listed as
> predominately zone 7, with a small portion being zone 6. Don't know
> where you live in Delaware, but if you look it up in a seed catalog, you
> might want to get your magnifying glass. It is difficult to distinguish
> the borders.
> These zones are related to average minimum temperatures in that area, &
> thus give an idea of what plants will be winter hardy there (though you
> probably already have a pretty good idea of what will, and won't, grow).
> Sincerely,
> Kathy Haggstrom
> Anchorage, AK
> Zone 3
> hagg@alaska.net
It's probably worth adding that the Arnold Arboretum has published a
commonly used (Wyman's garden Encyclopedia, M. Dirr's books) and
slightly different zone system, so when reading you need to be sure
which zone system your author is using (it should not only say so in the
intro, a copy of the relevant zone map will almost certainly be printed
somewhere in the book. The other standard caution is that the USDA and
AA zone maps only advise of the range of customary minimum winter
temperatures - they do not tell you anything about other factors which
have to do with winter hardiness - amount of drainage or wind protection
a plant may need, for example, or the difference between USDA Zone 5
(minimum temps of between -10 and -20) in an area that gets a heavy snow
cover that does not melt all season and the same temps in an area where
snow cover is spotty and the ground is constantly warming up and cooling
down at the surface. Beth Metty, Munith, MI, USDA Zones 5B, 4A,
dependiong on the winter