Not Coffee Grounds: The Overlooked Scrap That Makes A Fantastic Tomato Fertilizer

Savvy gardeners know that you don't need to rely on garden centers only to support your plants; rather, you can often find solutions right at home. For example, potato peels. You can use the kitchen scrap to give your tomatoes a major nutrient boost.

Tomato plants are known to be heavy feeders. In order to grow to their full potential, tomatoes require a balanced supply of NPK: nitrogen, phosphorus, and potassium. Potato peels can help with the K, potassium, and provide some phosphorus, too. Speaking to the Cleveland Clinic, registered dietician Anna Taylor, RDN, LD, said of potatoes, "Potatoes are good sources of potassium, as long as you leave their nutrient-rich skins intact." That certainly applies here, as we're only talking about using the potato skins.

That said, before you bury those fresh potato peels as a budget-friendly tomato fertilizer, take a pause. Just adding the peels to the soil can turn problematic, as they can not only attract pests to your garden, but they could also end up sprouting themselves under the right conditions. This can happen with compost piles, too, when the peels aren't sufficiently buried. So what can you do instead? An alternative is to add the potato-peel nutrients to your tomato plants in liquid form.

Turning potato peels into a liquid fertilizer for tomato plants is simple. You can do it in a couple of ways. One way is to steep the peels in boiling water, just as you would tea leaves when making tea. However, unlike tea, you won't use the potato-peel liquid until it's actually turned cold. Tea Epicure describes the steeping process for tea as "the process of extracting the soluble compounds from the tea leaves and dissolving them in water." In the case of potato skins, steeping will help extract the peels' rich nutrients into the water.

To use it, simply separate the cooled down liquid from the peels and use the homemade fertilizer to set your tomato plants up for success. Alternatively, you could make a potato-peel liquid fertilizer by simply keeping the potato peels in a container of water for about a week or so. As with the tea method, you'll want to strain the liquid from the potato peels first; but rather than use the liquid directly, you'll need to dilute it first as it'll have a thick consistency (e.g., 5 parts water to 1 part potato-peel liquid).

Note that tomatoes need potassium right before and during fruit production. It's generally a good idea to fertilize your tomatoes every one to two weeks during the growing season.