I always enjoy walking through the greenhouse during the busy season. There’s something about seeing all the colorful baby plants that makes me feel hopeful about the future! We now have two greenhouses where we plant the seeds that we’ll later transplant out into the field. Starting most of our crops in the greenhouse instead of planting directly into the field has several advantages. For one, germination is never 100%; it typically ranges from 50% to 90%. So planting seeds directly into the field means that you can either have huge gaps in your field–an inefficient use of space–or you need to plant the seeds more closely together than you want the plants to be, then go through and thin the field out later—a waste of both seed and labor. A second advantage to the greenhouse for the young starts is that they can be coddled, with some protection from extremes in weather and regular watering and fertilizing exactly when they need it. Plus some plants like warmer temperatures for germinating, and we can put those on a heated pad.

But probably the greatest advantage to starting the crops in the greenhouse is that they get a head start on the weeds. Weed competition on an organic farm can be fierce, and labor spent combating weeds is probably the most significant cause of the increased cost of organic produce over conventional. Conventional farms often apply herbicides to kill weeds, and plant into a “clean” soil bed with nothing growing in it. That’s not the sort of farm ecosystem we are after, of course, but it is certainly frustrating when the farm is busy as can be and the weeds take over a plot of young radishes because we weren’t able to get in at the right time to weed.

Weed control has many aspects on our farm, from using our cultivating tractor and hoeing by hand, to watering up weeds and killing them either mechanically or with the flame weeder before planting the crop. Starting crops in the greenhouse first means that when we do plant them out they at least have a head start. The weed seeds will germinate as soon as we start watering the plot, but the starts will have the advantage of height and vigor, and have a chance to shade out and otherwise outcompete the weeds.

So today I am appreciating the greenhouses, so vibrantly packed with colorful new life, which is getting ready to enter the big world outside.

*This article was originally run on May 20, 2014

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