(Image credit: Shutterstock) Summer is almost here, and it is the ideal time to get planting. If you prefer the taste of fresh, homegrown tomatoes, why not grow your own tomatoes from seeds or in pots ? Not only is this natural choice chemical-free, but it’s also a cost-effective way to cut down your grocery bills. Perhaps the biggest challenge many face is how to get the most out of their crop and increase yield for a bumper harvest. In fact, tomatoes are known to be heavy feeders, needing a substantial amount of nutrients to support healthy growth. These essentials include potassium, zinc, calcium, nitrogen, and phosphorus — all of which can be found in common kitchen scraps that we usually throw out. I recently found a surprising yet simple way to help your tomato plant flourish, and give it a healthy boost without relying on the usual fertilizers or viral tomato-growing tips . What’s more, this kitchen ingredient is a staple for everyday cooking — so be sure not to throw out your onion peels afterwards.…