I’m sure everybody was tired of the snow and icy weather by February of this year, but as a farmer the worst part was the lingering cold through April. With the summer temperatures the past few weeks, it is easy to forget how cold this year’s spring was. The ground did not warm up until well into April and it seemed like there was a frost or freeze warning every night. This kept many farmers sidelined and unable to plant crops until well into April, which means delayed harvests and a shorter spring season. Over the years, spring has proved challenging with it’s temperature swings, heavy freezes, early heat, or torrential downpours. These types of weather patterns are what keep farmers awake at night wondering if they chose the right profession. While spring can still be challenging, we have learned many techniques over the years to tip the balance in our favor and combat some of these weather extremes. We used to use many of these techniques when we were home gardeners and have simply scaled them up to fit a larger farming operation.
We have two main techniques in the spring time: High tunnels, and low tunnels. High tunnels are the large structures you see as you drive past our field. These structures are steel pipes covered in plastic with doors on either end. We can enter these tunnels and work inside of them because of their size. Contrary to popular belief they are not heated, therefore, we grow seasonal crops inside of them (no tomatoes in February). So how do we do it??? We start in January, usually right after the new year by preparing the soil and beds for planting. The soil never freezes because the tunnel is covered in plastic. On a cold January day, the sun can heat the tunnel to 70 degrees creating a warm spring like climate. We only plant seeds in January, such as carrots, beets, lettuce mix, peas, etc… We can not transplant live plants because the tunnel loses all of it’s heat at night and a live plant grown in warmer temperatures is not used to the extreme cold of January. Think of a person living in Florida all his/her life moving to Siberia in the winter time. This person would not be too happy! But a seedling that germinates in the cold weather is immediately acclimated to those temperatures and has no problem surviving. There is a catch….when the seedling germinates the nighttime temperatures in January could hover around 0 degrees. When the sun goes down, the tunnel will lose most of it’s heat and the plant may get too cold and die. Therefore, inside of the tunnel we suspend fabric frost blankets over top of the plants every night. This fabric traps the heat trying to leave the soil and keeps the plant warm enough to survive these challenging temperatures. You can think of it this way…the tunnel itself transports the plant to Maryland type winter temperatures. When we cover plants inside of the tunnel, now the plant has been transported to Georgia winter temperatures. The second benefit of the tunnel is keeping the wind from buffeting the plants. Plants are like us- they feel wind chill. But the tunnel blocks the wind and the leaves only feel the cold temperatures without the wind. We all feel warmer on a 32 degree day without wind, than a 42 degree day with 20 mph winds. Every morning we walk in the tunnels at 10:00 and take the covers off the plants to allow the sun to heat the soil for another day and every afternoon at 3:00 we cover them up once again. These structures also allow us to protect plants from the early weather swings in March and April giving us a chance at beautiful harvests of greens and root crops in the early spring.
If I was reading this, I would have two main questions: doesn’t a plant need sunlight to grow, and how could I do this in my garden? Yes, a plant needs sunlight, and it does grow slower in January, but it still does grow! If you look on a world map, and trace a latitude line from Alburtis, Pennsylvania to Europe, you will find we are on the same latitude line as Spain and Italy. These are countries known for warmer sunny climates. Therefore, we do have enough sun to grow our crops in Pennsylvania even in January. But how do you do this in a garden? Next week I will discuss low tunnels which we use on our farm and are similar to high tunnels, but a much more affordable way to generate early crops for the home gardener.
This week's share consists of:
Full Share- arugula, radishes, carrots, swiss chard, pak choy, scallions, hakurei turnips, red beets, head lettuce and broccoli
Half Share- arugula, carrots, swiss chard, red beets, head lettuce and broccoli
What can I make with my share this week?? Here are a couple of ideas!
Beet and Arugula Salad- This is one of our family favorites and you can substitute scallions for the shallots! http://www.foodnetwork.com/recipes/giada-de-laurentiis/beet-and-goat-cheese-arugula-salad-recipe.html
Broccoli and Carrot Salad- http://www.inspiralized.com/2014/06/22/summer-broccoli-carrot-slaw-salad/