Solar cones were inspired by the glass cloches used by the French since the time of Louis XIV, and possibly earlier. They help retain heat and moisture, and they protect seedlings and plants from wind, insects, and animal predators. They also help warm up the soil in spring and fall, and can be used in winter for such crops as kale.

Photo taken from the book "Solar Gardening" by Leandre and Gretchen Poisson.

Pictured here are solar pods the authors use to extend the growing season.