The plan is to start seeding in the greenhouse this Saturday. The forecast for Sunday is a high temperature of 12 degrees and a low temperature of 1 degree. Something doesn’t seem quite right here…but fire up the propane furnace we must, because mid-month is the time when we seed the crops that take many months to mature, such as shallots and leeks, and those crops that we want to harvest as early as possible in the spring (bok choy, lettuce, baby beets, and swiss chard).
All farming is part science as well as art, and this is especially true in the delicate environment of the greenhouse. You might think that raising plants in a completely climate-controlled environment is straightforward and easy–far from it! Problems with pests and diseases can be much more severe in the greenhouse than in the field. Aphids, which are preyed upon by myriad beneficial insects outdoors, can rapidly multiply on tender transplants in the greenhouse. White flies, thrips, and fungus gnats also thrive in the warm moist environment. Rather than spraying for these troublesome pests, we work with a biological laboratory that specializes in Integrated Pest Management (IPM). Throughout the spring, we receive shipments of beneficial mites and wasps to re-create the usual checks and balances found in nature.
Moisture management is a constant challenge with transplant production–too little water stunts plant growth and uptake of nutrients. Too much water creates an ideal environment for fungi and bacteria that cause the roots and stems of seedlings to decay. Throughout the early spring months especially, we have to watch the forecast carefully to decide when and how thoroughly to water transplants, taking in to account the size and type of plant we are tending. While conventional growers use sterilized potting media to avoid disease problems, the philosophy behind organic production emphasizes plant health through the complex interactions of soil micro-biology. Therefore, we use a compost-based potting soil that may contain harmful fungi and bacteria, but also contains the beneficial organisms necessary for healthy plants.With daily watering, nutrients quickly leach from the small pots in which we start our seedlings. Every two weeks or so, we “top dress” each plant with a fertilizer mix containing dried manure and minerals. This too requires great care and experience: too much fertilizer can burn plants as the salts in the manure extract moisture from plant tissues. Too little fertilizer leads to yellowing starts that may never fully recover, even after being transplanted into the field.
I am always eager for the season to begin with the first sowing of onion seeds mid-February. It is wonderful to watch the greenhouse fill up with lush green plants, even as the greyness of winter lingers on seemingly forever. Yet, I am always filled with a bit of trepidation this time of year. By mid-April– when nighttime temperatures are still below freezing and long before we enjoy a harvest from outdoors–I will have seeded the majority of our spring and summer crops. I have experienced the cycle from seed to abundant harvest for 8 seasons now, but I still examine the first emerging seedlings with awe and disbelief; the first harvest of each season seems as miraculous as our first crop six years ago. As much as I’d sometimes like to nail farming down to a precise science, there is a special joy in the mystery of farming as artistry.