A lot going on in the garden...

Spring is such an exciting and ever changing time in the garden.  This year is no exception.

New birds are arriving daily, others are nesting, including red breasted nuthatches, northern flickers and black capped chickadees.  All the nest boxes have cameras, and as the action heats up I will stream live video form each (now we are streaming from inside the nuthatch box http://www.ustream.tv/channel/red-breasted-nuthatch).

Just yesterday, 3 nuthatches hatched.  Here is a short video of them getting one of their first meals.

And of course, I have been busy with garden projects.  Here are some photos of what is happening now and some updates on projects...

Featured prominantly on the wall of my shop- I keep a list to remind me of the projects I want to complete.  

This floor grate was an early one on the list (I made it this winter from old wrenches) and replaces a dilapdated, temporary wood grate I made several years ago.  Beneath the grate is our compost furnace.

The greenhouse is really filling up.  

And so is my little nursery.

I have been growing these sedum (Sedum lanceolatum)  for a green roof on the chicken coop I will be building...

 

The coop will occupy this space- the corner raised bed in the vegetable garden that gets too much shade to be really productive.

In the meantime, these shovel chickens enjoy the space.

In what has become a rite of spring, we moved our composter.  This change was set into motion by our new back gate, and fence rearrangement, that was prompted by storing our camper in the garden (click here for my wife's blog about our camper- a project in itself)

It fits right in. 

My plan is to build a pergola over it.  On the list.

 New garden furniture has been on the list for some time. And this winter I made a lot of progress. 

 Several new shovel chairs and benches replaces our dilapidated bent willow chairs.

 Even the birds got new furniture- a new bird bath to match the chairs and gate.

Winter greenhouse wrap up

It worked.
As I have started to spring- and summer-ize my greenhouse I figured I should do a winter greenhouse gardening wrap up. Going into the winter I was really curious how my design and all the thought and planning would work out for my- I mean, my wife’s- greenhouse. In the end I am very pleased with how it performed this winter. However, we did learn a lot too, and armed with this knowledge, I am excited for next fall and winter. Too bad we have to deal with spring and summer. A few weeks ago, I removed insulation from the windows, re-installed the solar window openers, removed the cold frames and started planting a lot of seeds in the greenhouse (native seeds from my list of 2010 Garden Projects, see photo of the flats at the beginning of the post) .Here were our goals for the greenhouse: essentially to grow cold hardy vegetables in an unheated greenhouse all winter, without supplemental heat.

What worked:

• The greenhouse design with insulated north wall and north roof, steeply pitched south-facing roof, added winter insulation, compost furnace, barrels of water, and cold frames all worked well to achieve our goal of having the greenhouse stay above freezing through the winter (click here to see the winterization of the greenhouse). We only heated it with an oil filled electric radiator for four days when temps were below -10 F. Mainly the reason I heated it on those days was because I was afraid of the water barrels freezing and if they did they would end up cooling the greenhouse of weeks or months!


• The Compost furnace produced heat, and the compost composted all winter.


• The solar pool cover storm windows- I like this design so much I am going to build something similar for the shade cloth this summer- removable framed panels. I’ll keep the solar pool cover panels on for another few weeks.

What didn’t, or what to change for next winter:

• We started many of the vegetables that we grew int he winter too late, this year we will start them in August rather than in October or November to get trough the winter and be productive all winter. There is so little light from mid Dec-mid Jan so we can't count on too much plant growth during this time (I know I read that many times but I had to experience it to understand it, I guess).


• Pot up more herbs from the vegetable garden and bring them into the greenhouse in the fall earlier
  -I did this with mint and chives, but I probably could have done this earlier


• I never did add a storm door- maybe this summer I’ll add a storm/ screen door combo- I guess I have to add this to the 2010 Garden project to do list.

Greenhouse weatherization, and germination report

The greenhouse has been doing well, especially since we've had a relatively mild fall so far. It has been a lot of fun extending the gardening season- before the greenhouse we would have been long done vegetable gardening by now. Despite the relatively mild fall I have been keeping busy with winterization tasks. I built another cold frame for the other half of the ground bed (see photo below), installed the solar pool cover for insulation (but not how I expected- read below), and activated the compost furnace.

Frankly when I got the solar pool cover I didn't really have a plan to install it. I had only read about them on blogs and greenhouse gardening forums, and it seemed like if you have a greenhouse in Zone 6 or further north, you had better get one. So I did.

To make a long story short I ended up just making storm windows from the pool cover- easily removable and installable panels for the roof (see photo above). I installed the bubbles facing out (with the pool cover installed on the inside of the greenhouse). I purchased a diamond clear 12 mil pool cover, essentially really heavy duty bubble wrap. I chose the 12 mil for a good balance between light transmission and insulation (negative relationship there, unfortunately). As far as I can tell the R value of this cover is about 3 (regular bubble wrap R value is around 1/ inch of thickness). I like this storm window design so much I think I'm going to make frames and install the shade cloth this summer the same way, rather than on the outside like I did last summer- it is really nice and easy to install and looks tidy.

I finally activated the compost furnace, read: filled it with leaves. With just leaves and some water, it is already close to 120 degrees F, and providing heat radiating up into the greenhouse. Ultimately, we are going to try for a C:N ration of about 30:1 to produce more heat. Maybe though we will get closer to 15:1. The leaves we have on hand from street trees will make up the bulk of our Carbon load (along with sawdust from my woodworking shop), and I am on the lookout for some hot manure, chicken, or llama, or something.

All the plants are growing well in the greenhouse, and already we have planted a second and third round of salad greens, and radishes. Also, a new item for the greenhouse is cat grass for our burgeoning population of elderly, slightly defective, used, house cats. Although our newest cat, June (see below, and yes this is a cat, and yes that is a real picture), likes to lick cardboard, I thought I could grow her something more enjoyable to chew. Perhaps next week we will have fresh salad greens and so will our cats.

Greenhouse Winterization, part 2

The transition to the winter greenhouse garden continues....

We removed most of the cold intolerant plants, but kept a few Thai pepper plants that had some flowers and fruits on them, and they are still doing great. Frankly, I was happy to get rid of tomatoes for the year. My wife transplanted the broccoli and brussel sprouts into the ground bed that I started in flats, and she filled the rest of the ground bed with spinach, lettuce, carrots and radishes.

As far as projects to transition to the winter greenhouse, I installed two 55-gallon metal drums filled with water to act as a heat sink and thermal mass, but also to provide water for our watering needs. It was gratifying to fill these from our rain barrels, and this begins the winterizing of our rain barrels and their transition to downspouts for the winter.
Unlike the plastic olive barrels we use for rain water harvesting, the barrels we re using in the greenhouse are metal (for thermal conductance), black (for solar gain), and also act as good shelving and work surfaces. These are reused drums (clean) and are about $20 from Axmen

We’ll see how these work, only having 110 gallons of water will not provide nearly enough BTU’s to maintain the greenhouse above freezing alone, but coupled with other features, hopefully it is enough to provide benefits. Water, though a good heat sink, would need to be in a volume close to 500 gallons, based on the square feet of glazing and insulative value of my greenhouse, to have a significant effect if that was the only thing I was relying on to keep temperatures moderate. If nothing else, however, the metal drums do act as shelving and storage for water.

Other changes for the winter:
I disconnected the solar window opener on the east window, and covered the east and north window with 2” rigid insulation, the silver film will also reflect a bit more light to the greenhouse.

I installed a cold frame over 1/2 of the ground bed (see below). This is essentially a greenhouse inside the greenhouse. We'll see how it works, and I'll probably cover the other half of the ground bed- but right now it is an experiment- stay tuned for temperature data.

Left to do:

Install solar pool cover to south facing glazing
Install storm door

Activate the compost furnace

More posts coming soon...

Greenhouse Transition to Winter

With temperatures expected to be around 6° F in the next a few days (yikes!), it is time to transition the greenhouse from summer to winter. Right now, the greenhouse is over filled with Thai peppers, eggplants, basil and tomatoes - all plants that are not too cold tolerant. Some of these plants are in the ground beds in the greenhouse, some are in pots that we had growing outside this summer.

It is still very warm in the greenhouse during the day when the air temperatures have been in the 40's. Our goal is to grow hardy cool season vegetables in the greenhouse in the winter.

When the nights began cooling, I moved our potted eggplants and peppers from outside into the greenhouse and I also dug up and potted many of the Thai peppers we had growing in our outdoor raised beds. This totally filled the greenhouse.

It has been a great summer and start to the greenhouse life, and we are looking forward to more to come. The pepper and basil harvest is so much better inside the greenhouse that next year we probably won’t grow any outside or those that we do, we will grow in pots so we can bring them in when the nights get cool. We did this this year and we got several more weeks out of our peppers.

There is lots to do for the greenhouse for the fall/ winter:
I started seeds for broccoli and brussel sprouts already (see below), these will go into the ground bed, once the tomatoes, eggplants and peppers are done. Next up (maybe tonight) I'll start spinach and lettuce that we'll grow in flats on the greenhouse shelves. Later, we'll plant radishes, carrots and the broccoli and brussel sprout starts in the ground bed. I will also make a cold frame for the in ground bed- this will add more insulation for those vegetables (about 10 degrees F, or about 1 zone). I also need to add a solar pool cover for insulation to the glazed south wall, and some metal 50 gallon drums to the north side for water and solar mass. Soon we activate our compost furnace - stay tuned for the results there.

Lots to do, the cold really snuck up on me this year.

Construction update: bird nests and greenhouse

Bird nesting updates:

The Black capped chickadees hatched yesterday (May 5), and this puts them just about on schedule for a typical fledging time of around June 3.

The northern flickers are still courting (and stuff I can't mention here), and the male is still doing a little bit of excavating. I think the female may have laid the first egg yesterday (May 5) and is beginning to incubate

Greenhouse construction update:

This weekend, I installed the floor (recycled 100-year old Missoula brick, see below), and framed the four walls. All the framing lumber is from Home Resource in Missoula and most is recycled lumber, the rest is sustainably and locally harvested.

All the framing members that will be exposed- either inside or outside the greenhouse were primed and painted (2 coats), on all 6 sides prior to installation (primer and paint also from Home Resource- $5/ gallon!).

In the photo below you can see the grate over the compost furnace in the floor. This is actually a temporary one, one to use while I finish construction so I don't fall in... again. The grate is slatted to allow warm air and CO2 from the compost to rise into the greenhouse.

To the south (to the right in the picture below) of the brick floor is an open area that will be a raised bed. Hopefully this weekend I will frame the gable ends and even the rafters.

Heating the greenhouse

I have gotten a few questions about whether there is enough mass in my compost pit to heat the greenhouse, and frankly I don’t know, but probably not (see below). Although there is a lot of physics involved and there are easy calculations, there are a lot of variables that lead to uncertainty and imprecision, too, such as the following:

• Outside air temperature
• Composition of compost
• Type of manure
• Mixture (C:N)
• Type of carbon - e.g., straw, sawdust (generated from my woodworking shop)
• Frequency of turning the compost pile
• Frequency of C or N addition
• Size of greenhouse
• Insulation of greenhouse
• Thermal mass in the greenhouse (water, concrete, etc…)
• Other sources of heat

I have been researching this quite a bit, and although there are some great resources out there, I think the bottom line is I am going to have to try it and see how well it works.
Two great sources are the Physics of Composting by Cornell (it seems they have the answers to everything ) and “The Composting Greenhouse at New Alchemy Institute: A report on two years of operation and Monitoring March 1984 - January 1986”.

I based my calculations largely on the results from the above report. In essence, they used an active system to draw heat from a 25-cubic yard compost pile to heat a 576-sq. ft. hoop house. Their compost pile was composed of horse manure and sawdust (though it is not the hottest compost mixture, it is probably what I would use, plus our releatively insignificant contribution of kitchen scraps). This system gained them 23-35°F over the outside ambient winter temperature on cold, clear nights. The temperature at the highest point in their greenhouse dropped to 28°F (which I think was the lowest it got), but it did not cause problems for their lettuce (good news to me).

There is a huge range of information out there on how much compost can heat (see variables above). I estimate I will typically need between 4,100 and 8,000 BTU’s to heat the greenhouse to above 32°F in the winter (here is a great tool to begin determining your heating requirements). The range I am using in heating requirements is based on heating from low temperature between 0°F and +17 °F. Even though it does get to –30°F here, the average low temp is 17°F according to (http://www.weather.com/weather/climatology/monthly/59801?), and I used 0°F as a realistic good middle ground. I look at this range as designing for 90-95% for the time, rather than the 5% event. These BTU calculations have taken the glazing material, glazing surface area, insulation and greenhouse design into consideration.

Here are a few bits of information from various sources:

• A compost bin will produce about 1,660 BTU's/ cubic yard/ hour or 1,530 BTU/ lb
• Or heat 6-24 square feet of greenhouse/ ton of compost (interestingly, both these ratios seems validate my ratio below, too)

Another way to calculate how much compost I would need to heat the greenhouse is using the example greenhouse (from the Composting Greenhouse at New Alchemy Institute, above) because their results seemed to work for my needs. Using the ratio of of their greenhouse square footage to the quantity of compost they used was 576:25 so using that ratio, I would need about 2.6 yards of compost. My planned compost furnace is about 1 cubic yard, so my compost furnace would, in theory, supply 1/3 the heat to keep my greenhouse going in the winter.

In addition to the compost heat source I will use rain barrels as a heat sink, but perhaps more effectively, as a source of water for the plants in the greenhouse. Given the space restrictions, I will probably only use 100 gallons, or roughly 1/5 of what I would need to heat the greenhouse with passive alone (though I'd like to find out more about Glauber's salts or related). In addition to water, I will have a concrete floor, but again, the concrete will only account for a very small fraction of passive solar heating needs. The roof on the south side of the greenhouse is angled to intercept the low winter sun angle effectively (as opposed to standard, conventional kit greenhouses), so hopefully that will help. To better insulate the greenhouse, I will seasonally install a solar pool cover. I will have a ceiling fan in the greenhouse to help move the air around and finally I will rely on a thermostatically controlled oil-filled electric radiator-style heater (about 5,200 BTU’s). The heater is large enough to heat the greenhouse alone, since I roughly need between 4-8,000 BTU's (depending on outside temperature)with no other assistance.

So, knowing that one method alone will not effectively (or in the case of the electric heater, sustainably) heat the greenhouse in the winter, hopefully a combination of techniques will yield satisfactory results. Again, the main thing here is that I have no desire to grow orchids or tropical plants. In the winter I am only hoping to grow hardly vegetables- and I think I can do it with little use of the electric heater.

Greenhouse

My newest garden project is a greenhouse. I have spent this winter researching and designing a small (6x10') greenhouse for our backyard. It is the greenhouse project that is largely responsible for this blog- to share ideas and get help from gardeners.

Our greenhouse will be used year round; we plan to use it to extend the growing season by a couple of months for our usual vegetables and in the winter we plan to grow hardy vegetables- nothing too fancy or exotic: lettuce, spinach, Brussels sprouts, beets, and similar. I love hot Thai peppers and this is another reason for the greenhouse, to fulfill my peppery dreams.

We do not plan on heating the greenhouse much, but we will to keep it above 35- 40 in the winter. One interesting thing we are planning is to heat the greenhouse with compost. I am not sure if it is going to work, but I am going to give it a try. The worst case scenario is we will have storage in the greenhouse and compost that actually decomposes in the winter.

For our "compost furnace" I am planning to dig a 3x3x2 ' (deep) pit in the floor of the greenhouse that will act as the compost pit. The walls will be lined with plywood and 2" rigid foam insulation so heat does not get lost to the ground. Over the top will be an expanded steel grate to walk on and allow easy watering and ventilation. I am not sure if there will be enough mass to really heat the greenhouse, but at least the compost will break down faster than it does outside in our backyard.

The rest of the greenhouse is going to be made from recycled materials as much as possible, and I have already begun accumulating various pieces. Even though I won't start building the greenhouse for a few months, most of the pieces I have had to collect ahead of time so I could design the greenhouse. I have all the windows, doors, exhaust fan, lighting, and more.

The greenhouse will be small- mainly due to our small lot, but hopefully it will be well designed and efficient. The north wall will be conventionally framed with 2x4's and insulted with r-13 fiberglass bats, the north end of the gable roof with be constructed similarly. The south wall the south slope of the roof, will be glazed and about 50% of the east and west walls will be glazed.

I am still working ion the details of the foundation, but in any case it will be insulated with 2" rigid foam, and there will be a concrete floor, except on the south end where it will be opened to the ground for a raised bed.

Soon I will post some drawings of my greenhouse plans and pictures of the piles of materials that are filling up my woodworking shop.