As you look over your site this winter, consider all aspects of the micro-climates you have in your garden. How much direct sunlight will strike the soil and warm it in March? Hint: the direct sunlight is the same as it receives in late September. This amount of solar heat in spring may be enough for your lettuce to germinate a couple weeks earlier than if it is in shade. If your garden is on a slope, the cold air will travel down to the lower areas, delaying the growth of your early plantings. Could a retaining wall collect the cool air and perhaps direct away from your tender plants? Even a trellis or an artistic sculpture can give protection to a tender perennial, when placed in the right spot.
Besides tracking sunlight and cold air, think about the winter rains. How well does your soil drain? Is it too soggy wet in the spring? Is water pooling anywhere? Can you direct that surface water into a rain garden?
If cold, wet soil is a problem for your early gardening efforts, build up some raised beds. This would allow the soil to warm sooner and be dryer for earlier spring planting. Some people build up their beds by constructing wooden or brick frames. Others just mound the soil by shoveling the soil from the path areas into the planting areas to create your beds. If the garden area is new, the added “top soil” from the paths will allow for a deeper root zone. Make your beds flat on top and narrow enough (maybe 3 feet across) to easily plant/harvest/weed them without stepping into them. This allows the soil to stay loose because your feet won’t compact the soil.
In a raised bed, plants can be spaced more compactly than the row cropping you see in a field. Soil amendments and manures can be added to just the raised bed area, rather than covering the whole garden. You will be surprised at how much sooner the soil temperatures increase in raised beds. In addition, these beds can be covered by low tunnels of plastic or other types of cloches to really extend the growing season. There are many cloche designs using wire or plastic hoops that support a simple clear plastic, acting then like a “mini greenhouse”. I’ve used recycled glass windows formed into an A frame and tied to supporting stakes. Lots of useful items can be collected for free and used to enhance the heat in a small garden.
While studying seed catalogues this month, pick out your Allium seeds first. Onions and shallots are easy to grow in our climate, if you start the seeds indoors in January or early February. We usually select sweet onions (like Walla Walla), storage onions (like Copra), Shallots (like Ambition), red onions (like Mars) and then some sort of cipollini or Italian type. Seed thickly in clean 4 inch plastic pots, using a sterile seed mix. I may sow as many as 40 seeds in each pot. They germinate pretty quickly at 60 degrees on a heat mat. Give plenty of light and keep moist. At about 6-8 weeks as the little green shoots are starting to tip over and tangle (3-4 inches tall), harden off the pots in a cloche or unheated greenhouse.
Prepare your onion beds with lots of manure and additional bone meal if you have it. The soil should be light and as well drained as possible. Then when warmer weather is predicted (40 degrees at least), carefully plant out the little green thread like onion starts. Tip out the pots and begin to separate the onions, using care not to tear off all the roots. I have been impressed at how few roots they can have and still begin to grow in March. The basil disc where the roots grow from is the important part to plant. I plant them just a few inches apart and then in April, begin thinning out the green onions to serve in salads and cook as spring onions. I use my hori hori knife to carefully remove the young onions as they begin to crowd each other. By June, the onions should be at least 5 inches apart as they grow to full size for August harvesting. If the leaves have slight yellowish tinge in the spring, give them an application of a liquid fish emulsion fertilizer diluted with water. If they aren’t dark green by mid May, give them another application. We plan our harvest to have enough onions/shallots to store and last the whole winter, storing them in a cool, dry, dark shed or closet.