The New USDA Zone Map-What it means to Your Garden Now

This week the USDA released a new Plant Hardiness Zone Map in the United States. And it's all due to Global Warming, right? Well, not exactly. Here is the new national map with "halfzones" noted, in other words to regions of five degrees Fahrenheit either way- According to the official USDA Website,differences in length of time of recording conditions and more technologically elaborate reporting play a part in the current rendering of zone differences:

Compared to the 1990 version, zone boundaries in this edition of the map have shifted in many areas. The new map is generally one 5-degree Fahrenheit half-zone warmer than the previous map throughout much of the United States. This is mostly a result of using temperature data from a longer and more recent time period; the new map uses data measured at weather stations during the 30-year period 1976-2005. In contrast, the 1990 map was based on temperature data from only a 13-year period of 1974-1986.

Some of the changes in the zones, however, are a result of new, more sophisticated methods for mapping zones between weather stations. These include algorithms that considered for the first time such factors as changes in elevation, nearness to large bodies of water, and position on the terrain, such as valley bottoms and ridge tops. Also, the new map used temperature data from many more stations than did the 1990 map. These advances greatly improved the accuracy and detail of the map, especially in mountainous regions of the western United States. In some cases, advances resulted in changes to cooler, rather than warmer, zones.

Because of my location in the Missouri Ozarks, this post will deal with Missouri. You can download the map for wherever you live in the United States here. The region which includes Missouri, is the North Central region. Here's that map: What does it mean to you as a gardener? The main differences that I can readily see are:

• Some of Southern Missouri is now Zone 7!
• Some of Southern Missouri is 6b where it was formerly 6a. And so forth.
• With 13 zones in the United States, and these halved to "a" and "b" zones you can pretty quickly see that Missouri is still considered moderate in climate here compared to the rest of the US.
• This will make a difference in some species of plants for your garden, or at least in some cases, in more options for you.
• If over the years, you've had to rule out some "borderline" plants that you love, regroup! Compare your plants/plant packets with the zone numbers and don't rule out any species until you do that comparison.

Here is the State of Missouri with its shiny new zone designations! :) The USDA cites other uses for these zone maps too. They are important on several scientific levels:

While about 80 million American gardeners, as well as those who grow and breed plants, are the largest users of the USDA Plant Hardiness Zone Map, many others need this hardiness zone information. For example, the USDA Risk Management Agency uses the USDA plant hardiness zone designations to set some crop insurance standards. Scientists use the plant hardiness zones as a data layer in many research models such as modeling the spread of exotic weeds and insects.

Enjoy your weekend, and keep poring over those seed catalogs! :) ~JB The United States Department of Agriculture website is referenced in the above included images and blockquotes.

Testing Flower Seed for Germination

 I harvested an enormous amount of Autumn Beauty Sunflower Seeds in 2009. The weather was not ideal. There had been a lot of rain!  I had read that if you harvest them out of the seed head before they completely dry (and therefore develop) that the germination would be much poorer, but this had to be balanced against the fact that the birds then beat you to the harvest, in many instances... or even worse, that the mold would ruin them, so, I opted with getting the seed, in the first place. I carefully saved them, took the "extra" stuff out, and dried them down slowly. There was a half pound or so.   Later that winter, I ran my own little germination test on them.

The quick and dirty way to do that is:

• Take a given number of seeds, say 100, or whatever sample you feel will be indicative of a big enough sample to get a good reading, and lay them in a paper towel.
• Wet the paper towel, to mimic garden soil moisture, fold it around the seed, to cover them, and  put the whole thing into a ziploc bag on your kitchen counter or somewhere out of the way.....and check it beginning at three days until they sprout.
• After the "sprout period" for your type of seed has passed, count the number sprouted, take that as a percentage of the whole number you sampled, and voila! A percentage of viable seed is determined.

 My tests on my sunflower seed that I harvested was quite good for the species, I'm told, at around 75%,  sure enough, I had a plethora of sunflowers that year!  Price some of that seed....it's pretty expensive, making me all the more proud that I had some of my own.  Autumn Beauty Sunflowers, by the way, do breed true as they are not hybridized.  That makes it possible to save the seed with expectations that you will grow what you intended. :)

The Taxonomy (Science) of Garden Seed Germination

I find the actual process of seeds coming to life, or actually, anything in our world coming to life fascinating- so much that I have studied it over time, whether it was an academic assignment or just me, wanting to know from a personal level.....how stuff works. ;)

Here are diagrams of the wondrous process first with tomatoes, then other types of seed as shown.

The actual process of tomato seed germination.  I find this stuff fascinating....but then, I'm an agricultural/horticultural/floricultural geek girl. :-D



The taxonomy of other types of Seed Germination.....the Garden Bean, Pea, and Corn.