The days are growing longer and it's time to harvest the summer's bounty. All the tomatoes, peppers and other vegetables are reaching the end of their growing season. While it's fun to eat all of this, sometimes there is sadness too. If you have a raised bed garden box, you can use it to extend your growing of greens/vegetables into the winter.
Make a cold frame out of your raised bed garden box. You will need some extra lumber, nails, hammer or a drill, screws and heavier gauge translucent or transparent plastic sheeting. Attach the lumber to the box on three sides with the longest side being the highest point, attach a wood slat across this and then attach one piece of wood on each of the shorter sides so it slopes down to the level of the wood box. This way, you will have the angle for the plastic to be attached over. Staple the plastic around the base but leave the lowest side open and secure with rocks or heavy pots. Do this so you can open the cold frame and check on the plants.
Usually there will be condensation on the inside even when it gets really cold. You may have to add a little water and plant food if this isn't sufficient. Hopefully, you've got some southern exposure of sunlight too. With the plastic sloping downward you should not have too much of a problem with ice or snow collecting. The snow can act as insulation if it gets really cold and some light does still get through. The best plants to leave in a cold frame are hardy greens like kale and chard and some root plants like radishes and beets. Using this method, one can extend the growing season well into the winter.