Pea gravel and pebbles can weigh down windowboxes. Empty water bottles are a lightweight option. Place rinsed bottles inside the planter and add soil on top of them. The space between the bottles will allow proper drainage without the extra weight.
My grandmother has been making this sweet, chewy, delicious pie for years and we all love it! Perfect for Thanksgiving or any party year round. Clickthrough for the full recipe and more delicious dessert ideas.