20 Insanely Clever Gardening Tips and Ideas (with pictures!) - Epsom salts in the soil for tomatoes and peppers. Add a Tablespoon or so in the soil when first planting and then sprinkle more into the soil when mature.
For the north side of the deck, on the grass. Would hide underneath the deck and help with Mosquitos. Lemon grass is a natural mosquito repellent and grows quite tall. Plant it in large planters next to a patio to create privacy and repel mosquitoes.
Flower Rocket - The effortless way to grow flowers! Enjoy colorful annuals all summer long by slipping the pod in a pot of soil, then water - how easy is that? Website has other interesting ideas, from pods to rolls of seeds.