Tomato plants grow with such speed and vigor that it’s easy to be tempted to keep feeding them, thinking that we need to add nutrients for all of that new growth our plant has put on. But the truth is that over-fertilizing tomato plants is just as bad as under-fertilizing them.

Over-fertilized tomatoes develop lots of green growth at the expense of fruit production. And as if that isn’t annoying enough, all of that tender green growth is like a dinner bell for nearby pests and a magnet for disease problems. Under-fertilization results in slow plant growth and poor fruit set, as well as blossom drop and fruit drop.

So, how do you strike the right balance between under- and over-fertilizing your tomatoes? It’s actually pretty simple, and something you only really have to worry about twice during the growing season. (Less work!)

Fertilize at Planting

At planting time, I like to add a bit of compost the the planting hole, as well as several crushed eggshells or bonemeal to fend off blossom end rot. If I have it on hand, I also like to add a bit of granulated organic fertilizer to the soil at this time.

Fertilize at Fruit Set

When you see your first tiny fruits start to form on your plants, it’s time to do the second fertilizer application of the season. This is when I break out the fish emulsion, and give each plant a good, thorough foliar feed, as well as the soil around each plant. This will provide valuable nutrients just when your plants need it most.

Supplemental Feeding

If you find that production seems to be dropping off, or your plants just look “tired,” there’s no harm in giving them another foliar feed with the fish emulsion, or with compost tea or manure tea. This can be done once per month during the growing season to keep the plants growing and producing well.

Good Soil = Good Tomatoes

As with any kind of gardening, success with growing tomatoes starts with the soil. You will want to grow your tomatoes in rich, fertile, well-drained soil with plenty of organic matter. Incorporating compost and composted manure at planting time, as well as mulching with organic mulches such as grass clippings or fall leaves will make a huge difference — and every year, the soil will just keep getting better.

It seems like it’s not enough; that it should be more complicated than that, doesn’t it? But that really is all there is to fertilizing your tomato plants. Most years, we don’t bother doing a supplemental feeding, and, to be honest, we’ve even forgotten to fertilize at fruit set a time or two and everything has turned out fine. One less thing to have to fuss over — always a good thing!