use a box and just put small watermelon into it with lid open so vines can grow out, takes all season but keeps pests away and makes a great square watermelon! Farmers, Pumpkin, Boxes, Squares Watermelon, Gardens, Squarewatermelon, Sugar Baby, Square Watermelon, Growing Watermelon
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How to grow watermelons: They do not like "wet feet" but they need at least an in of water each wk. You can trellis up watermelon plants, and once the plants set fruit, support the burgeoning melons with slings, which can be made with cheesecloth, nylon stockings, or old T-shirts. If the sling completely covers the fruit, it provides protection from insects. In addition to saving space, trellising improves air circulation and helps prevent disease.
Square Foot Garden. Very well organized, like the companion plants, good mixing of different nitrogen pulling plants throughout the space, wouldn't place the potatoes and watermelon in a square foot garden like this and I don't think they listed supports for the peas.