Thursday, September 30, 2010
As I was planning out the summer version of my container garden this year, I asked myself the question “how can I have FRUIT?” I plant lots of greens in the spring and fall, and I always have plenty of aromatics, but my family is particularly fond of fruit, and summer is the season for lots of fruit. The problem for me, constrained to a container garden as I am, is that most fruit takes up lots of space. Make a list of all of the fruit you can possibly grow in a temperate climate, and you will find that a very large percentage grows on trees (apples, peaches,etc.), bushes (blueberries, raspberries, etc.), or vines (grapes, kiwi, etc.). All of these are perennials and take lots of space and time. Then you have the cucurbits (melon, cucumber, squash). Those are annuals that produce lots of fruit, but with the exception of a few cultivars specially bred for containers, most are sprawling vines that take lots and lots of space. At my house, anything that ventures beyond the safe confines of the actual container gets eaten by the local wildlife.
The problem comes from the energy expenditure required to make fruit. Sunlight is used to convert carbon dioxide and water into sugar, and that is done in the leaves. The more fruit you have, the more sugar you need, the more leaf surface area you need. So fruit-producing plants tend to be large.
I decided this year to try something new and see if I could find a fruit that was an annual but didn’t take up too much space, and the deadly nightshade family seemed a good place to start. After all, the nightshades are known for medium-sized plants that produce an abundance of fruit. The only problem is that the majority of the plants in the nightshade family produce fruit that, botanically speaking, is fruit, but culinarily speaking is considered a vegetable. Tomatoes, eggplant, tomatillos, and peppers are all nightshades. Potatoes are also nightshades, but the little green berries are poisonous, so I am not going to try them and see if they are sweet or not.
A little research revealed two likely candidates: ground cherries and sunberries. Ground cherries are a close relative of tomatillos, but are eaten more like berries, They are described as being about the size of cherries, but with a papery husk like a tomatillo and a flavor that is sweet. Sunberries are small, dark blue berries somewhat resembling blueberries. The descriptions I was able to find ranked anywhere from “kind of bland raw, but delicious cooked” to “incredibly delicious and addicting.” I figured both would be worth a try and I ordered some from Seed Savers Exchange, which is a really good site for hard-to-find seeds. Unfortunately, I didn’t order them until late May, so planting in pots and transplanting after frost wasn’t really an option. No matter, I just wanted enough to try them, and I saved enough seeds to grow them next year.
Both plants started off well and needed to be thinned by the middle of July. Shortly thereafter, they started setting fruit, despite each sharing a pot with a particularly exuberant cherry tomato that got huge but produced little fruit. I did at least manage to prune the tomatoes somewhat so that my ground cherries and sunberries could get a little sun.
The final results were mixed. I have to say that both types of plants produced lots fruit for the size they got. The sunberries were rather bland. To me they tasted like a kind of bland, earthy tomato. They were low on tartness, sweetness, and flavor. I never got enough at once to try actually cooking them, but I wasn’t really looking for something that needed lots of flavor added to be good anyway. I am glad I tried them, but I won’t grow them again (anyone want the rest of my seeds?). The ground cherries, on the other hand, were an instant hit. I got Aunt Molly cultivar, which were described as having a citrus flavor. I’d say it was a pretty accurate description. When you bite in, you get a burst of sweetness and a little citrus flavor. As you chew, though, the sweetness gives way a little to something a little more savory. My friend Robert called it buttery, which I suppose is about as accurate a description as I can come up with. At any rate, it has a depth of flavor that I particularly enjoyed. I will definitely be growing ground cherries in the future. The nice thing is that supposedly, given and early start and plenty of sun, it is supposed to grow into a bush about 3’ tall and similarly wide. If the density of fruit on that plant is similar to my smaller bush, one bush should produce plenty for snacking.
Monday, September 27, 2010
So once I get this greenhouse built, what would I do with it other than grow vegetables? Well, it will still be several years before I get it up and operational, so I have plenty of time to work out the details, but here are a few of my ideas:
Growing Mushroom Logs
In Arizona, the key to growing mushroom logs seems to be 3 things: 1) lots of moisture, 2) keeping them out of the sun, and 3) protecting them at least a little from earthworms. In the greenhouse, I am planning a living path to walk on, with plants growing on it. The water from the beds will drain straight into the soil here, so it should be almost constantly moist, but still have good drainage. It will also be at the base of a 3’ high wall, so it will not get much sun. I can line mushroom logs along the wall and it should be near perfect growing conditions. All I would have to do is bury them about halfway in the soil and leave them alone. It will give me an opportunity to replenish my supplies of a couple of kinds of medicinal mushrooms, grow some new kinds, and grow lots of my favorite edibles. I will also have a lot of great soil for growing some of the types of mushrooms that grow well in soils, such as shaggy manes. I might even be able to get king stropharia mushrooms to grow. That would be quite a coup.
Maintain a Small Ecosystem
My vision has always been to have a complete ecosystem in my greenhouse. Obviously I will have lots of plants and plenty of living bacteria in the soil. I will also put a lot of beneficial fungus in there, from saprophytic fungi making me mushrooms to eat and improving the soil, to mycorrhizal fungi that helps the plants to thrive. But I also want an animal component. I need insects to pollinate my flowers. Windows without screens should do that pretty well. I also need beneficial insects to eat the pest insects that find their way in. That isn’t too hard, though. There is an easy source of vast quantities of ladybugs nearby that I can collect every fall. There are plenty of praying mantis about that I can capture and release in the greenhouse as well.
I also want larger animals in there, though, but what to do? Lizards are easy. I could do anoles, a childhood favorite (but how do I keep them inside?), or I could go the easy way and go with the local whiptails and fence lizards. An iguana, basilisk, or water dragon would be cool as well. Turtles would be cool, but I think I will have too much vertical relief and they don’t really climb. There are also birds. A parrot (I favor macaws) or a small group of bobwhite quail as pets would be cool. Chickens produce eggs. The big problem with birds is that two of the windows to the greenhouse will be my bedroom windows, so noisy birds are pretty much out. There are also some neat mammals that would go well in a greenhouse. Rabbits would produce large amounts of fertilizer, but would have to be kept in a cage if I have any hope of growing anything. The cage could go over the compost pile, though, and add a constant stream of extra nutrients to the greywater headed out to the beds. A sugar glider or flying squirrel would be so cool in there. I just haven’t come to any decisions yet on that. I just want SOMETHING in there.
As I mentioned before, I am going to have some sort of water feature. It won’t be very big, though. Should I make it just a sterile tank, a holding place for rainwater, or should it be a living system? How much room do you need to grow tilapia for food? Maybe I could get native frogs and toads to come in and breed there. Maybe I just have turtles or catfish. There are so many options on this one.
A Wetland Water Filter
I have mentioned before that I plan on using compost to filter my greywater before it heads out to the plants. When I originally planned that one, it was to double as a compost bin for everything but the kitchen scraps. However, I now have a tumble composter that does a really good job of handling just about everything I can throw at it. I don’t necessarily need the extra compost space, so it will be extra effort to keep it full and functional. Wetlands have been used for years to filter water. They are excellent at filtering a large number of impurities from water. It also happens to be an ecosystem that I know next to nothing about but have been very curious about for some time, so it would give me an opportunity to learn and experiment. It also might take less space since the compost bin was supposed to be 2 bins. If I could make the water filtration area smaller, I would have more room to grow more plants.
I have been a big fan of carnivorous plants since I was a child. The problem is that Arizona is just too dry. Even sitting in a puddle of water, the plants dry out quicker than they can absorb water. A greenhouse might just keep the humidity high enough that they would survive. That would give me an opportunity to grow some of the larger American pitcher plants as well as a variety of sundews and maybe even a Venus flytrap or two. The trick is to keep the water level up. I think I can manage that by putting them in a floating bed on the water feature. I could put it on runners and situate the floats so that it floats at the right height to keep the water level just right. As the water in the tank drops, so does the bed. If I decide not to have any sort of aquatic life in there, this bed could be the entire top of the water feature.
A 10’x20’ space is barely enough to grow everything I want to grow, and sprawling, vining plants, like melons, are just too much for the space. However, if I can create some trellises and arbors, I just might be able to get some of those plants to grow vertically. In addition to saving space, it must might help shade the walls of the house in the summer as well.
Epiphytes, or air plants, have been another of my loves over the years. Epiphytes grow on other plants, needing no soil. I currently have several epiphytic orchids and bromeliads and would love to expand the collection. In particular, I would love to grow a vanilla orchid, which I hear get very large, and I MUST HAVE a dragonfruit cactus. An epiphytic cactus that produces fruit is just too awesome. Actually, I would love to have a Meyer lemon tree and grow the dragonfruit up the lemon tree. I also really want a staghorn fern. Those are amazing, majestic epiphytic ferns.
Anyway, those are a few of my ideas. As you can see, this greenhouse won’t be so much a greenhouse for me as a bioneering laboratory.
Thursday, September 23, 2010
Sunlight is going to be an interesting concern in my greenhouse. Immediately to the east, I will have a screened porch. That means that I won’t get much sun first thing in the morning. Immediately to the west, I have a large juniper tree. That will steal a lot of my evening sun. Since I am facing 22 degrees west of due south, though, I think I should get some really good sun through the rest of the day.
Due to cost considerations, I will most likely have to forego installing the glazing for several years. When I do, though, I have a new set of concerns. I have specifically designed the house for passive solar design. In the summer, I am protecting the house from the sun as much as possible by providing as much overhang and shading as I can to the southern wall. In fact, if you notice, on the house itself, the second floor hangs 2’ over the lower floor. In addition to that, I have a set of wooden slats that give additional shading. During the winter, the sun comes in at a much lower angle, allowing the sun to come in the windows and warm the house. Once I get the glazing up for the greenhouse, I have another source of heat: the greenhouse itself. In the winter, the sun will warm up the greenhouse, producing heat. I will open the upper and lower windows from the house into the greenhouse. As the air heats up, I will rise and enter the upper windows. That will pull air in from the lower windows. This creates a convection current that heats the house. I will also have high and low windows on the glazing for the greenhouse so that I can use the same convection current to dissipate heat to the outside in the summer.
Thermal mass is another big consideration in my greenhouse. Thermal mass is a large, dense structure, such as a body of water or masonry that has the ability to absorb heat. As the day heats up, the thermal mass slowly absorbs the heat, tempering just how hot it can get. By the end of the day, the thermal mass is warm, but the outside temperature starts to cool down. The thermal mass will slowly release that warmth back out. In a house, a thermal mass is stored in the exterior walls, absorbing the heat from the outside and releasing it back to the outside in the summer. Sometimes thermal masses are used on the inside of houses in the form of concrete floors or walls, usually set back enough that they get little to no summer sun, but lots of winter sun.
I will be taking advantage of a high thermal mass in the greenhouse. My raised beds will be constructed of cinderblock. I am also considering using river rock and mortar to create a more aesthetically pleasing façade to the cinderblock. All of this creates a good thermal mass to help the greenhouse hold its heat on cold winter nights. I will also have the water feature in the corner that will provide a lot of thermal mass. I probably won’t want to let the greenhouse suck the heat out of the house on winter nights, so it will need to have a way to keep itself warm. A good thermal mass should do that, releasing the heat close to the plants. I must say, though, that I will be seeing how well this works before putting any temperature sensitive tropical plants in there. In the summertime, I need to find a way to keep the thermal mass from becoming a liability. I am hoping that I can use vines for this. The soil in the path will allow me to grow peas or pole beans or something similar and let it grow up the walls, thereby shading the walls from the sun. Cucurbits growing on top and cascading over the walls would also work. This should help limit the thermal gain in the summer. Also, the sun will be striking the walls at a more oblique angle, which should also help. I will probably use some sort of trellis to protect the side of the house as well.
All in all, I think that the greenhouse will use its sun efficiently and help keep my house warm in the winter. My only worry is that it will also help keep it warm in the summer. I need to prove to myself (and more importantly, my wife) that it will work as needed to keep things from getting too hot in the summer. I think I will probably end up installing an evaporative cooler on the side of the greenhouse as a backup plan. I have also considered having some sort of system that will allow me to have roll-up blinds that I can use to shade the inside of the greenhouse at certain times, or even partially shade it more often. If I get something that is cloth, it could be used as a shade to keep heat out during the summer days and a blanket to keep heat in on winter nights.
Monday, September 20, 2010
So now I have talked about how I am going to lay it out and how I am going to get water into and out of the greenhouse. Next I am going to have to have something to grow all that wonderful produce in, some sort of wonderful soil. Now, I could just buy a load of topsoil and hit the ground running. But that would be cheating. For someone who engineers with biology, the soil is by baseline, my starting point, my most important factor. Yes, I need good, fertile soil. But more importantly, I need living soil. For that, I want soil that is almost 100% compost.
I am fortunate to live in the neighborhood I live in. I have a nearly inexhaustible supply of organic material right out my back door. The ecology of my back yard is chaparral, a dry, scrubby landscape dominated by scrub oak. And yes, scrub oak really is oak. It stays small and twiggy and is easily chipped up in my little electric wood chipper. It also grows really densely. I could go out daily and maintain trails, reduce fire danger by removing brush that’s too close to houses, and take it from dense patches. Then I bring the trimmings back to the house and chip them up. Between the sheer amount of scrub oak and how fast it grows, I doubt anyone would ever notice that it was gone. And those that did would probably appreciate my maintenance work. I certainly wouldn’t be clear-cutting anything.
Once home, the chips would be pasteurized and inoculated with culinary mushrooms. Many of the best culinary mushrooms really grow well on oak. So I could grow some in pots or even in the beds themselves. If I can get several blocks completely inoculated with mushroom mycelium, I could create a bed with fresh chips and then break up the blocks and use them to inoculate the bed. With any luck, I would have many pounds of tasty mushrooms as the first crop from my garden. When the mushrooms have gotten what they want out of the wood chips, they get fed to the worms, who will finish them off to make high quality compost in just a month or two.
Now, I have to say that the prospect of harvesting and chipping about 10 cubic yards of scrub oak is seriously daunting. Fortunately, I have a few cheats that allow me to get a quick start. First of all, there is straw. It is a little less dense than wood chips, but it is also readily consumed by a wide variety of culinary mushrooms. A bale is only about $4, so I can get them in bulk pretty easily. So that will probably be my starter method. For my second cheat, I have another readily available resource. During monsoon season, my neighbors and the neighborhood in general spend a considerable effort cutting and removing weeds, especially tumbleweeds. I can just walk around the neighborhood pulling weeds. The green matter will help with the composting as well as improve the nitrogen content of the soil. The best part is that I can use all weeds, regardless of whether they have gone to seed or not. As the raw materials compost, the level of the top of the beds will drop considerably, which means that I will have to keep adding more and more material until the decomposition has slowed down. Assuming I fill it with weeds fairly early in the process, any seeds in the mix will end up so far underground that they will have no chance of pushing to the surface once they sprout.
Once I have gotten the beds a little over half full, I need to start paying attention to the makeup of the soil. I will test it and start looking for amendments. Most of the best soil in the world has one thing in common: it contains large quantities of mechanically weathered rock. The fine rock particles have lots of minerals in them that are readily available to plants. They also have good staying power in the soil. So I will do a lot of looking around at this point and see if I can find a good source of greensand and rock phosphate to supply the potassium and phosphorus I need in my soil. I don’t know of a good rock-based source of nitrogen, so I will probably have to get some blood meal. I will certainly be using lots of compost, which should help. I have some friends with chickens, too, so chicken manure will be added. I will also have to start taking drainage into account around this time. If my soil doesn’t drain well, I will start adding sand or pea gravel to the mix. If it drains too well, I might just add a little unused clumping kitty litter, which will help plug some of the holes and retain water. Clumping kitty litter is made from expansive clay. Caution is recommended with this method, though, as a little goes a long way.
Once I have a fairly decent level of soil that has composted well enough to support plants, I can also plant green manures. Something like alfalfa or hairy vetch would add lots of nitrogen to the soil. I could also begin selectively planting food crops at this point. The greywater distribution system would probably not be fully buried in the soil yet, so any crops that grow food on the ground or in the ground, like zucchini or carrots would be out. However, crops like corn, sunflowers and pole beans that raise their crops well above ground would be a good choice. In addition, these crops produce lots of compost when they are done.
Eventually the final soil level will be reached and will be fairly stable. I fully expect this to take 2-3 years at least. It isn’t until this point that I can consider planting perennials. Any time before that the constant sinking soil level and constant addition of more mulch and compost would be death to anything that would be around a long time.
Thursday, September 16, 2010
In my last entry, I covered how to get water into my greenhouse, but not how to get it out. To be honest, I have put almost as much thought into draining the greenhouse as I have in watering it.
Obviously, the water hits the soil first, so soil is a significant consideration in drainage. I suspect that I will have to do some serious adjusting to my soil mixture for drainage purposes. If I make it drain too well, it will pass the water straight through before the plants have a chance to get any, and no amount of water will be enough. If I make it too dense, it won’t drain fast enough and will always be a puddle, which would kill the plants. They say that if you have clay soil and need better drainage, add organic matter. They also say that if you have sandy soil and need better water retention, add organic matter. It loosens stiff soil so water can penetrate it and it helps absorb water passing through sandy soil to improve retention. Based on this, I am intending on making my own soil almost entirely out of organic matter. I may adjust it a little this way or that with some pea gravel or clay kitty litter if it needs some help.
From there, the water drains down to the bottom of the beds. My plan is to make the floor of the greenhouse concrete. I just don’t want all that water draining right under my foundation. I also don’t want local trees to put some roots up in my greenhouse to steal all my water and possibly damage my beds. So concrete bottom it is. The beds, which will be about 3’ high, will be made of cinder block. On the bottom course of the interior walls, I will leave the mortar out of the vertical joints. This will allow the water to drain from the beds into the pathway. The pathway will also have soil on it, about 8” deep. There will be a perforated pipe inside a sleeve of landscape fabric running the length of the walkway. I will put a cinderblock block with chunks knocked out every 2’ or so along the length of the pipe, straddling the pipe. I will then mortar a stepping stone of some sort to the tops of the cinderblocks. The rest of the walkway will be filled with soil with some sort of shade and moisture tolerant creeping ground cover. Personally, I am hoping for Corsican mint, but to date my attempts to grow Corsican mint have been considerably less than successful. I am also hoping to put some mushroom logs in the pathway there as the shade and moisture will be perfect for them.
So the water trickles down through the soil and then drains to the center of the greenhouse, where it encounters more soil. From there, it drains into a pipe that will take the excess water off to the natural area behind my house. Depending on how much water I have there, and what I can convince the neighborhood of, I might just put in another distribution system and a little orchard of fruit trees. We’ll see.
Monday, September 13, 2010
This is part 2 of my design for my greenhouse. Part 1 is here.
When I had a nice big garden at my last house, water was a serious source of contention between my wife and me. Though we never did the math, her contention (probably rightly so) was that we spent more money on water than we got in benefit from food. It is just too dry here in Arizona. So in my design for my greenhouse the design of water was crucial. Now it is not to say that I am going to have a low water greenhouse. If that were the case, I would only be growing cactus and such and I really don’t want to do that. No, in this case, the concepts we are going for are wise use of water and a distribution system that reuses water wherever possible. For this, I have a two-pronged approach to water. Yes, I will have a spigot in the greenhouse, but it is my sincere hope that I will almost never have to use it. The vast majority of my water will come from either greywater or rain water.
Here in Arizona, we have a blanket permit for using greywater. That means that, as an individual homeowner, I have the right to use my greywater without getting an individual permit. I am expecting some friction from the local municipality since they like to use the treated water to recharge the aquifer, but I am a strong believer that it is better to not pull it out and treat it in the first place than it is to pull out twice as much as you need and then put half of it back. Most people I have talked to seem to think I can squeak it through.
There is one problem, though, that becomes a major design concern. The blanket permit has a few stipulations. The one that really affects my design is that you cannot surface irrigate food crops with greywater. Honestly, this just makes sense. Whatever dirt you just washed off your hands shouldn’t end up back on your food. So I am taking a two-pronged approach to this problem. The first prong is to filter the water to get as much out as possible before it waters my plants. That should get rid of the hair and dirt and a lot of the soap before it gets distributed to the plants. To do this, I am going to use compost to filter it. The exit of the greywater system will be right next to the back door. The line will run under the sidewalk and dump straight into the compost. The compost bins will be fairly shallow and despite not being shown this way in the drawing (one level of detail I didn’t feel like doing), will be a little above the rest of the beds.
There will be two compost bins with a filter cloth of some sort between them. The water will flow into the first bin, flooding it, and then trickle into the second bin. From there it will trickle into a filtered tub in the corner where it will enter the distribution system. Since I have a dog and don’t want the greenhouse to be smelly anyway, the compost used for filtration will be strictly a repository of wood chips and plant waste from the greenhouse, with no food waste in it. I’ll try to put living mushroom mycelium in there to help with filtration, but I anticipate difficulties keeping it alive for very long. This will mean a non-smelly compost that has lots of microorganisms in it to help grab the nutrients out of the water. It will also mean that the water leaving the compost bins will be a sort of weak compost tea that will be composed of very little leachate.
The distribution bin will have two outlets, one that goes to the central bed and one that goes to the outer beds. From there, the pipe will run along the inside of the wall of the bed that is next to the path, about 6” below the surface of the dirt. There will be an outlet with a valve every two feet or so along the edge. That should give me a fairly even distribution of the water. If I have an area that is not planted or getting too much water, I can turn off zones as I need to.
One of the problems I have struggled with is the even distribution of water. If each outlet was at the same elevation, the dirt at the beginning of the system would get most of the water and the end of the line would get almost none. I plan to remedy this problem by having an inch or two rise between the bottom of the distribution pipe and the outlet of each outlet pipe. That way the pipe fills up before it starts to distribute water, so it should distribute fairly evenly.
The distribution system for the central bed will be similar to the one for the outer bed.
2) Rain Water
I am going to do my best to capture as much rain water as I can for the greenhouse. I am hoping to bury some sort of tank on the northwest side of the house that captures rain from at least half of the roof of the house. 300 to 400 gallons would be good, though I am going to try for as much as I can. I am also planning on putting some sort of water feature on the northwest corner of the greenhouse, though I haven’t decided what form that will take yet (just a big tank or a living system?). The overflow of the large house tank will go to the greenhouse tank to make sure it is full. From there, the overflow of the greenhouse tank will dump into a terracotta channel mounted along the edge of the outer raised bed wall. This terracotta channel will be grouted to the wall and tilted towards the soil. Assuming I can get it all level, it will fill up and then spill over into the dirt, acting sort of like a trench irrigation system without using any of my precious growing space.
A rainwater source and distribution system will be crucial to this working. Since I can’t surface irrigate with greywater, I need a way to water seedlings and other plants whose roots don’t go deep enough to take advantage of the greywater. The water feature will also have a spigot on the side for filling a watering tank. Then I can just top off the greenhouse tank with water from the house tank.
Ideally the combination of the two systems will serve to keep the greenhouse watered without too much effort from me and almost no use of additional city water. In fact, I did some research on how much the average household produces a day, and they say about 35 gallons of greywater per day per adult. Now we are pretty water conscious, so I’d say we are under that. However, with two adults and two kids, we’ll probably still generate about 50 gallons of greywater a day. That is probably more than I need. I might just have to turn the valve off half of the time and give the City its recharge water back.
Thursday, September 9, 2010
As a teenager, I discovered the joys of making terrariums. I started out trying to make a comfortable habitat for my pets, but it quickly became more about the habitat and less about the pets. That was the beginning of my love of engineering biological systems. As an adult, I realized that a greenhouse would be a terrarium for me and it became a goal to have one of my very own. But I didn’t want just any greenhouse. I wanted something intricately designed, efficient, self-sufficient wherever possible, and above all else, customizable. It would be a place where I could try out new ideas, tinker, and change things to make them work better.
A few years ago my wife and I bought a lot with the intent of building a house on it. Now that we are living in a rental unit on the lot next to our house and finally have our old house rented out, it is time to work towards building the new house. Naturally, the new house will include a greenhouse, though I suspect that the actual glazing will probably come along later. In the meantime, it will be a raised bed garden.
In the interest of making this a blog post and not a book, I’ll break up my design and intention for the greenhouse into parts. For starters, though, I’ll talk about the site layout.
The lot is kind of what we in Prescott call a “billygoat lot.” It is on a fairly steep hill and only covers 0.06 acres. Yes, I have the decimal point in the right place. The neighborhood is laid out with lots of open space and very small lots. That suits me just fine. As luck would have it, the lot slopes down to the south and the road is on the north side. I have about 15’ of fall from the front of the lot to the back. That means that when you walk in the front door off the street you are in the upper floor of the lot. Going down a floor and walking out the back still leaves you three to four feet above ground, just enough that I can put in a raised bed garden and still water it with greywater from the house. It also puts it in a good place to collect rainwater from the roof.
The greenhouse will be located on the southwest corner of my house and will be 10’ deep and 20’ wide. There will be a door into the house on the northeast corner of the greenhouse and the path into the greenhouse will start there with steps. There will be a 3’ wide bed all the way around the outside of the greenhouse, with a 2.5’ path next to it. On the inside will be a wider, deeper bed. There will be room for a bench as well.
Over the next several posts, I will cover the features of my future greenhouse, starting with water and drainage, then covering soil production and solar features, and finally ending with a discussion of some of the living systems I am hoping to build into the greenhouse once I get it fully built, glazed, and operational.
Thursday, September 2, 2010
It is September now, time to plant the fall garden in my area. The question is, what to plant. In order to determine that, first you need to realize how a fall garden is different from a spring or summer garden.
1) You plant when it is still hot, but the plant matures and is ready for harvest when it is cold. That means that plants that like to sprout in cold soil, like peas, are ill suited to a fall garden. It also means that plants that are frost intolerant, like tomatoes, are also out.
2) A fall garden is best suited to plants that mature quickly. When you consider “growing season” for your crops, it refers to the time between last freeze and first freeze. Many crops can take almost that entire time to grow, set fruit, and then ripen fruit. So crops that mature in just a few months are better suited to a fall garden. This often means vegetables instead of fruit (realize I am talking botanically speaking, which means if it has seeds, it is fruit).
3) If you have mild winters in your area (as I have in my Zone 7 garden), it works well to consider plants that may survive the winter. In some cases they will produce all winter long. In other cases, they will produce until winter throws too much at them. In still other cases, they will go dormant when it gets too cold, only to revive when the first warm weather of spring hits, giving you an early crop. Just remember that winter weather can be unpredictable, so you can’t necessarily count on that winter garden. But then again, summers can deliver hail and locusts as well…
Here are a few examples of crops to try in your fall garden:
Spinach – Spinach has been the star of my fall garden for many years. So far every time I tried it, it went dormant when the weather got too cold and then exploded into growth in the spring. It handles the cold like a champion. Most importantly, it stores whatever energy it can and grows explosively when spring hits. I often find myself trying to find a way to work spinach into every meal around the time everyone else is considering planting their garden.
Kale – All members of the cabbage family are known for their use of sugar as an antifreeze. Once the first freeze hits, they get a lot sweeter. I am particularly fond of Red Russian kale. It is a thinner, more tender kale that can be eaten in salads. However, during hot weather, it is bitter. It isn’t until the first frost that it becomes delicious. For me, this is ONLY a fall crop. Collards also fall into this category.
Broccoli – I once had a broccoli plant that had a rough summer and didn’t start producing until fall. When winter hit, it was undeterred by the cold and kept producing a head of broccoli once or twice a week until a particularly nasty cold snap around January finished it off.
Swiss Chard – This is another tough plant. It matures quickly, is very frost tolerant, and usually lives through the winter. The downfall of this one is that it comes back pretty anemically in the spring. After the winter, it is gearing up to produce seed. So come spring, pull out all but one of your Swiss chard plants, leaving the one so you have more seed.
Garlic – I have had great luck planting garlic in the fall and letting it grow through the winter. It will be ready for harvest around May or June.
Lettuce – Here is another plant that matures rapidly and is frost tolerant.
Cilantro – Cilantro bolts quickly in the heat, but it matures quickly, making it well suited to a spring or fall garden. Cilantro was another plant that surprisingly made it through the winter, only to resume growth in the spring.
Bok Choy – This is another member of the cabbage family that should be good for a fall garden, being both cold tolerant and fast to mature. I tried it for the first time last year and for some reason the plants got about 5” tall and went straight to seed. Not sure why. I plan to try it again this fall, though.
I have also had some failures in the fall garden. You may notice that a sizeable portion of the list above are greens. Anything that needs time to form fruit, big roots, a head, or some other part that isn’t just leaves may not have time to do so before winter sets in. I tried peas last year. They refused to sprout in warm summer soil, so the seeds took a full month to sprout. When they finally did, there wasn’t enough time to flower and grow pods before winter set in. The same thing happened with carrots and beets. I suspect it would be the case with cabbage as well.
Despite my suggestions, I would strongly recommend you experiment. It really is the best way to find out what works best for you and in your area. Even with mixed results you will extend your harvest through the fall and get to garden that much longer.