Hartley Magazine

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Be Prepared!

The greenhouse door after the stone hit it. The stone hit in the lower left corner. Fortunately, I had another pane of glass to replace the broken one. I was able to install the new door panel in a few hours.

We all know that people who live in glasshouses shouldn’t throw stones. Well, I have a new twist on that old proverb: People who have glass greenhouses shouldn’t use a string trimmer nearby. An unfortunate incident taught me this lesson.

Last spring, I decided not to weed between the slate stones of the patio that borders my greenhouse. How much easier, I thought, to let my string trimmer do the work. Everything went fine at first, with the weeds flying. But then suddenly the string trimmer kicked up a tiny stone, a pebble so small I couldn’t even see it. But minuscule didn’t matter. That tiny stone hit one of the greenhouse’s large patio doors with a startling, explosive bang, shattering the glass. Fortunately, the panel didn’t disintegrate and fall to the ground, so my cold-sensitive seedlings and tropical plants were safe from the frost predicted for that night. But it took four days to get and install a new panel.

This incident reinforced the Boy Scout motto from my youth: Be prepared! Unlike a good scout, I wasn’t prepared for the door to be shattered, or for that matter any of my greenhouse windows to be broken. When you have a glasshouse, lack of preparation about possible breakage can get you into serious trouble. And tiny pebble projectiles aren’t the only possible cause of a pane being broken. In winter, for instance, falling ice, a wind-blown tree limb, or a pile of wet, heavy snow could cause glass breakage with even worse consequences because of the winter cold.

So when you’re next in your greenhouse, look around and assess what might happen to the glass in adverse situations. If a pane shatters, do you have a spare the right size? If not, do you have a sheet of plywood to make a temporary patch? A sheet of Styrofoam can also be very helpful for covering a broken pane.

An additional concern when a pane of greenhouse glass breaks in winter is ensuring your plants stay warm. An insulating material like Styrofoam is useful in this regard, but you’ll also want the peace of mind in knowing that your heat source has a backup if it has to do some overtime compensating for missing glass.

Another incident last winter also pointed out that you need to be prepared. A power outage knocked out the electric heater in a friend’s greenhouse and with no backup system it resulted in a lot of dead plants. Gas heaters can also lead to problems. In the middle of winter, in the nearby city of Newport, the natural gas lines were over-pressurized, and the gas was turned off for more than a week. Several greenhouse owners did not have backup systems in their greenhouses and lost all of their plants. For this reason, if you have a gas heater, you might want to have an electric or kerosene heater ready? Yes, a kerosene heater may smell and put water vapor into the air when it’s in use, but that’s better than losing plants.

Check your greenhouse after a winter storm and if you have more than a few inches, remove the snow before it freezes or becomes icicles. Quite often the snow will simply slide off a heated greenhouse and pile up against the sidewalls. It will act as insulation, but an excessive pile of snow could break the side windows.

It’s also good practice to take precautions and eliminate any potential causes of glass breakage that you see. Trim back nearby branches at least once a year and remove the large icicles that might form on your greenhouse in winter. If the snow load is wet and heavy, remove it with a broom or long-handled brush. In many cases, snow will quite easily slide off a heated greenhouse because the glass is warmed from the inside. And don’t let wet snow pile up along the base of your greenhouse. It could buckle the glass sides if it freezes. Saving plants is all about being proactive and thinking ahead concerning the possible ways to safeguard your much-loved glasshouse.