Here is a little more information about my Alaska gardening experience; what I have learned so far and where I came from.
How I Got Here
I moved from Anchorage out to Wasilla in 2004 and started my Wasilla Garden Adventure. I am originally from Iowa. I have enjoyed gardening all of my life. I am learning that gardening in Alaska is very different then what I was used to. Follow along as I learn what it takes to garden up north. As Norman Vaughan said, "Life is an adventure!"
I came up to Alaska for a temporary summer job in 1991. In 2001 I met Marna where I work and became friends. We both enjoy gardening and we were encouraged by seeing many spectacular gardens and an explosion of flowers blooming all summer long. My background is vegetable gardening in Iowa and Marna’s background was flower and vegetable gardening in Northern California. We both found out very quickly that gardening in Anchorage, Alaska is very different than what we were used to. I tried my hand at container gardening in Anchorage. “My lettuce and Swiss chard did great, but my tomatoes never ripened”. Marna did a great job with flowers in pots and along the side of her house, until a moose ate her prized sunflower as she watched through the window. We both wished for more yard space to put in a real Alaska garden. In 2004 we were married and we bought a house near Wasilla and moved out of the city. In late 2010 Marna decided she preferred to live independently and we separated - ending our 10 year partnership.
The original front yard - plenty of room for a garden.
The new property came with a half-acre empty front yard and I was very anxious to get my hands in the dirt. In 2005 I planted tomatoes in large plastic tubs with the same poor results. Marna did much better with flower pots on the deck. I learned that our native soil was very rocky and made up mostly of gravel and clay – not the rich black Iowa loam that I was familiar with. I would have to purchase topsoil and start composting. I became an avid reader of any Alaska garden literature from the Alaska Cooperative Extension Service, Anchorage Daily News garden column, and the three Alaska garden bibles: "Alaska Gardening Guide" by Ann D. Roberts, “The Alaska Gardener’s Handbook” by Lenore Hedla and “Cold Climate Gardening” by Lewis Hill. I was very familiar with raised garden beds, drip irrigation, square foot planting techniques, and using mulch. But the reasons were not the same. In Iowa raised beds speed up soil drying during the wet rainy spring and in California’s long dry summers mulch preserves moisture and blocks out weeds. We usually get 100 - 105 frost free days here in Wasilla. Considering the extra hours of daylight is equal to adding an additional 20 days to our growing season. Although this far north warmth is as important as sunlight.
It's All About Conserving Warmth
Gardening in Alaska is all about conserving warmth. The soil is deeply frozen each winter and, despite our long days, does not completely warm up until mid summer. June 1st is our target date for setting out cold sensitive plants. There are many places where the soil never thaws, called permafrost. Using raised garden beds to catch the low angled sun helps the soil warm up much sooner. Using a soil thermometer will help you to monitor this warming process and remind you that despite warm sunny afternoons in May the soil takes time to warm up. Cold soil will only add stress and slow plant growth. Many seeds will just fail to germinate. It is better to be patient.
I decided to build large permanent vegetable garden beds 16 ft long by 4 ft wide by 16 inches high. You might notice the unusual angle of the beds. I took great pains to align the beds East to West as accurately as possible hoping to take advantage of the sun and speed up soil warming. The beds are staggered so that my future garden fence will run parallel to our house simply for aesthetics. I decided to build the beds out of pressure treated lumber. I had a lot of questions about using treated lumber. I believe it is okay based on what I was able to research on the internet. Working with treated lumber is not risk free. The risk is highest when handling the material during construction.
Rufus Chaney at the USDA reported. “There’s no evidence that food safety is impaired by growing vegetables around CCA-treated wood. High levels of inorganic arsenic in soil will kill a plant before there’s enough arsenic in the plant itself for you to consider not eating it.”
You must make up your own mind on this subject. I would have preferred to use composite plastic lumber or maybe corrugated steel panels – but the high cost and lack of availability were deciding factors.
Warming the Soil
In Alaska a deep layer of mulch acts as insulation and delays soil warming so traditional mulching is not advised. Using plastic mulch is a common practice and you can read more about it on the web. Black plastic mulch is successful at blocking weeds and conserving moisture – but contrary to common belief, does not warm the soil very well. Clear plastic works best for warming the soil, but as I found out, does not prevent weed growth. A new type of brown plastic both warms the soil and reduces weed growth. Called “infrared transmitting plastic mulch” or IRT mulch and you can purchase it from many good garden supply stores or on the web.
In addition to using IRT plastic mulch, growing many cold sensitive plants in Alaska requires a greenhouse of some kind. A permanent greenhouse is expensive so I decided to start with a simple hoop greenhouse made out of plastic conduit covered with plastic sheeting. My first project was a hoop tunnel over one of the garden beds. I quickly learned that on a clear day the tunnel could reach 100 degrees by 7 AM and ventilation becomes very important. Opening the ends or rolling up the sides became a routine. I have a drip irrigation system that works very well inside the grow tunnel. I have plans to add automatic timers for controlling water cycles. I tried growing tomatoes outside using plastic mulch – but the results were still disappointing.
In 2009 I added a full size hoop greenhouse for tomatoes. I had great expectations and started seedlings indoors on February 4th. By the middle of April I had 2 ft tall tomato plants in gallon pots all over the house. Many had bloomed and several had tiny green tomatoes. I built a greenhouse as soon as I could. I re-potted the tomatoes into 5 gallon buckets and moved them out of the house on May 3, 2009. The days were warm and sunny – but it was still frosty at night. I purchased a wireless home weather station and I could monitor the greenhouse temperature over the internet. It was scary to see the temperature slowly drop below 30 degrees at night many times throughout May. A simple plastic covered hoop greenhouse does not hold heat at night. All of the plants suffered from frost damage – but they all survived and I picked the first ripe cherry tomato on Memorial Day!
A small propane heater would have helped our Alaska greenhouse, but it worked and I had my first successful Alaska tomato crop in 2009. Ventilation was also as important as warmth. Opening the greenhouse each morning and closing at night was part of the routine. Adding automatic vents or a vent fan would be very nice. The varieties were all cold tolerant. We grew Sub Arctic, Early Tanana, and Glacier varieties suggested by the Alaska Cooperative Extension Service. They were all small salad or cherry tomato size. I want to try some larger slicing and canning varieties in the future. I grew Eggplants and Peppers in our grow tunnel and they also suffered from frost damage – but survived. I was also fighting a fungus problem. This was probably caused by the humid greenhouse conditions, crowding, and poor plant handling. I tried using a copper fungicide dust with some improvement – but I plan to switch to a new safer organic fungicide with early and regular application in 2010.
In 2010 I built a permanent greenhouse and it is still a work in progress. I am still using special greenhouse plastic film to cover the structure and have plans to replace this with polycarbonate panels. I designed it with a raised insulated floor and an insulated north wall to help conserve heat as much as possible. It has a solar electric vent fan and one solar window opener. In 2011 I added a small propane wall heater.
Alaska Garden PestsMany crops do very well in our cool sunny Alaska climate. I have had very good success growing lettuce, kale, snap peas, broccoli, and Brussels sprouts in uncovered raised garden beds. Except for one unique BIG Alaska garden pest - Moose!!! I have become accustomed to living with moose - even in Anchorage it is not unusual to find them anywhere at any time - walking down a busy city street - stopping traffic - or snoozing under a tree in your yard. The problem is that one moose has the ability to wipe out an entire bed of ripening broccoli in 5 minutes - usually the day before you are planning to harvest. And once they find your garden they will return often. Another lesson learned. But just how do you keep moose out of your garden? I keep strings of firecrackers by the back door - and they work when you are home. There are many suggestions - a very large mean dog , maybe - but the largest dog is no match for a hungry 1,000 lb moose. One expert stated simply - you can not keep a hungry moose out of your garden - if they are determined to get in. A very high and very strong fence works most of the time - but a moose is able to jump a 6 ft fence and can knock down almost any fence with little effort - even an electric fence. My first attempt will be to install a combination 5 ft high log rail fence with an electric fence above reaching 8 ft high in total. We shall see how well it works and keep you informed.
A major milestone was passed in 2009 with trenching in the electric service and the removal of a very ugly power pole located right in the middle of the front yard. I was finally able to proceed with some serious landscaping plans and I installed some additional garden beds. Work is always slower that you hope and there will always be more to do then is possible in our short Alaska summers.