Barbara, I have used hoop houses made of PVC pipe frames covered with 4 or 6 mm plastic to extend the harvest by growing earlier in the spring or later in the fall. You can use the same types of hoop houses to grow cold season crops all winter long if you want to. I suspect the hardest part for me would be to build one that could handle the hard north winds. If you are in town where there are other houses, other buildings like sheds, some fences and hedges, trees, etc. in close enough proximity to serve as a windblock, I think a hoophouse would be very easy to erect and maintain all winter. As Ilene mentioned, Eliot Coleman's "Four Season Harvest" is the classic book on the subject. One technique I learned from him was to use a frost blanket-type row cover on top of plants that then have further protection from a hoop house or high tunnel. That way, there are two layers of protection from the cold weather. However, Mr. Coleman, who is nothing less than a national hero to many farmers/market growers and serious hobby gardeners, has a brand new book out (April 2009) called "Winter Harvest" and even though it is primarily aimed at market growers, a serious home gardener could benefit greatly from reading it and applying his techiniques. People who've read both "Four Season Harvest" and "Winter Harvest" have stated in their reviews that basically "Winter Harvest" is an updated version of "Four Season Harvest" that includes what he's learned or changed or refined since he wrote "Four Season Harvest", so I don't know that you'd need to read both. Although, I do have to say that every word he's ever written in a book or magazine article or in any of the speeches he's given over the years is well worth reading! A couple of the most important things to remember about growing in a hoophouse or high tunnel or in short tunnels (more about them later) or cold frames is that you have to be able to open doors or vents to let heat out during the day or your plants will roast. Also, the larger the structure, the easier it is to maintain the appropriate temperature because very small structures heat up too fast and also cool down too quickly. You can use short tunnels that consist of wire or PVC hoops placed over garden rows and covered with floating row cover, plastic or both. They'll keep plants somewhat warmer, but not as well as a larger structure that has more mass. You can help increase their ability to hold heat by using a soil heating cable run down the row or plastic bottles spray-pained black and filled with water and used as solar collectors. I have used those big cat litter jugs spray-painted black as solar collectors in a hoophouse to protect early tomatoes from a late freeze with sleet and snow (and didn't lose a plant). If you use only a frost blanket type of floating row cover, I believe you pick up about 8 degrees of winter protection. With plastic, you can increase that and you can increase it a bit more with solar collectors. I haven't read "Winter Harvest" yet, but it is on my list of books to read before winter arrives. Finally, although some people have success using PVC framing, others may need to use electrical conduit as framing if they are in a high wind area or in an area where snow or sleet are likely. Another way to support a hoop house structure in those more difficult conditions is to use cattle panels as part of the support for the plastic roof. The Ardmore-based Noble Foundation has done a great deal of research into using hoophouses in agriculture. I've linked some of their data below that tells you how to errect a low tunnel. Also, you can cruise around their website or google to find their various instructions for making hoophouses (and raised beds) of different materials. Dawn Here is a link that might be useful: Nobel Foundation's Low Tunnel How-To

A solar powered bird bath heater is not practical. Painting the bowl black would have a bigger effect. It would convert 90% of the sunlight that hit it into heat. Solar PV panels are about 10% efficient (for light to elec to heat), so you'd need a panel 9 times the area of the bowl to have the same effect. It would also be very expensive. I have a thermostated one with a 60 watt heater. I've seen 44 watt ones that run continously, 44 watts x 24 hrs = ~1 kwH a day. My electric is about 5 cents a kwH in the winter (about 10 cents in the summer), so about 5 cents a day to run. Here is a link that might be useful: 44 watt heater

use plant saucers or thrift store/dollar store plates. For the base I use 4 in or larger pvc pipe cheap and easily cut. pick height and cut away..On one end I cut triangles off each side which makes stakes to push in the ground...not sure if that makes sense...the top part I gently trim so bowl /plate sits it...taller ones you can put rocks a brick or even cement in for stability...can paint, mosaic etc to match plate. Really creative can cut maybe 2 in holes on sides above 1/2 way point, fill pipe with rock or cement 1/2 way ,push into ground..then put in some dirt no higher than the holes..push in ivy or whatever from the side holes and plants will fill out for coverage for the birds before they land and as they are bathing..sorta like a strawberry pot idea. you can also get a solar spotlight with a panel put spotlight in pipe, panel in sun and a glass plate...so pretty all the best

Yes, I love the monarda/bee balm, Samuel. I've never been able to grow it very well. What is the secret to growing it? Ken, as the appraisers on "Antiques Roadshow" would say, your bird bath has patina. It's much more interesting and appealing to me that way. Good find. Jim, that is a cute little finch. Do you have a lot of them? We've got many, and they live in the three blue spruce next door. I love those guys and call them the Bickersons. They bicker and chatter up a storm. They like to live in climbing roses, and in my former home, they lived in the ivy that grew on the house. I didn't realize there were nests in the ivy until I got hit in the face with bird poopla that fell out of the nest as I was cleaning the ivy. Live and learn. Diane