Good news: It’s not too late to plant your tomatoes! Bad news: you need to do it NOW and you need to put a little elbow grease into it. It will come as no surprise that early summers in Seattle feel more like fall. For you, this means wearing warm layers you can put on and take off during the day. For tomatoes the same rules apply, but that sweater? It’s called a cloche.
A cloche is a small, translucent cover placed over plants to create a warm environment—on hot days it can raise the temperature around plants by a full 10 to 12 degrees. Cloches work especially well on heat lovers like tomatoes and peppers, and can be made from a variety of materials. Every June first, I plant tomato starts and build small cloches over the beds.
To build a cloche, head to your local hardware store and pick up:
1 length of 3/4” PVC, cut into 10-12” lengths. (Most PVC comes in 10-foot lengths, so you will have 8 to 10 shorter pieces after you cut it.) These are used to anchor your cloche.
2 to 4 lengths of ½” PVC. These are thinner, flexible pieces of PVC and are used as the supportive ‘hoops’ for the cloche.
One 10’x25’-foot roll of 3mm clear plastic sheeting. This is the cloche material.
A package of zip ties to secure the cloche.
To build the cloche, hammer the ¾” PVC anchors into each corner of your bed and about every 3-4 feet across the length of the bed. Hammer until the top of the PVC is just about level with the soil. Make sure you mirror your anchors on both sides of the bed so they are positioned directly across from each other.
Place one end the ½” PVC hoop into a corner anchor and stretch it across the bed to the opposite anchor, creating a hoop support. Do this with all anchors, creating hoops, which will look like a covered wagon without the canvas.
Unfold the plastic sheeting over the tops of the hoops, leaving a 1-foot allowance on either end of the bed. Unfold the plastic down and around the sides of the hoops. Secure the plastic sheeting to the hoops with zip ties, leaving them a bit loose, so you can move the plastic easily up and down. (You will need to do this on sunny days so the cloche doesn’t get too hot and so that air can circulate around the plants.)
When you’re done, the plastic sheeting should be secure yet mobile, the hoops should be sturdy in the anchors and the plastic should cover all sides of the beds and insulate it well. If you’ve succeeded in all of these things, you’re golden! Make sure to water your tomatoes so the soil is consistently moist. Leave the cloche on until nighttime temperatures warm and the tomatoes are literally pressing up against the plastic—right about mid-July.