VW Hardy Zones

[arlingtondiver]

I am looking at the VW Plant Database and under VW Hardy Zones I see numbers all over the place.  For example, 1 - 10, 12 - 24, 29 - 45.  I am in the US so I'm familiar with USDA's zones but what are the others?  Europe has larger numbers but nothing like 24.  What are the upper range numbers referring to?

Marshall

[Monadnoc]

Here on the West Coast of USA some people use Sunset Climate Zones (from the Sunset Western Garden Book), https://www.sunsetwesterngardencollection.com/climate-zones/ , which go up to 24, I believe. They are a lot more detailed and take into account many more factors than the USDA zones. Maybe it's for them? Not sure what the 29-45 could be for?

 

 

Edited October 11, 2023 by Monadnoc

[Jeff Prince]

It's a data set from a variety of sources and is claimed to be following the USDA.

The plant database field is "VW Hardy Zone" and Vectorworks says this about it "1–11 (from USDA zone mapping)"

 

I wouldn't trust any data for hardiness found within Vectorworks as it is common to see values outside this stated range.  Most nurseries seem to have fed most data to Vectorworks using the Sunset system, presumably.  

 

The USDA Plant Hardiness Zones currently range from 1 to 13, but split the zones in half and use A or B to further describe them making 26 zones effectively.

The USDA zones are based on minimum temperatures, hence the mention of "currently" earlier.

 

Sunset actually defines at least 45 different climate zones currently, but you don't usually see anything that high.  It is a catalogue system where the number doesn't tie directly to something like minimum temperature like the USDA.  As a catalogue, it too could expand past the current numbering system.

 

The American Horticulture Society actually has a heat based system, but it's not typically referenced in gardening or landscape architecture.  It ranges from 1 to 12 currently.

 

See the problem here.

The best practice is for your office to decide how it wants to curate and maintain hardiness data and stick with a system that makes sense for your area.

With the pending abandonment of the Plant Database in favor of Plant Styles, I would maintain this data outside of Vectorworks in an database that can be used in any software rather than having all that data locked up inside a proprietary system like Plant Styles.   A database can power publishing software for making cut sheets on plants, spec writing, or custom plant books.  Vectorworks can't do that automatically or quickly.