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How To Fertilize Tomato Plants Right! Grow Your Biggest & Best Crop Ever

Looking for a great way to fertilize your tomato plants this year to grow your biggest and best crop ever? We have you covered with today’s article!

Tomatoes are one of the heaviest feeders of all vegetable plants in the garden. Not only do they require nitrogen, phosphorous and potassium to grow and develop, but they also need calcium, magnesium and a host of other micro nutrients to thrive and produce.

Unfortunately, no matter how rich and fertile your soil might be, there are rarely enough nutrients available to power an entire season’s growth to it’s fullest potential. That is, without providing your plants with a little boost of fertilizer.

best way to fertilize tomato plants
Young tomato plants need a bit of time in the ground to establish their roots before fertilizing. But once they do, a light and steady dose of energy can power them to a big crop.

When a properly balanced fertilizer is supplied to tomato plants, it can make a huge difference in their health and productivity.

But just as important as selecting the right fertilizer is knowing how much to use, and how often to apply it. Don’t give your plants enough nutrients, and they will struggle to grow and produce.

But on the other hand, give them too much power all at once or too often, and it causes them to concentrate all of that extra energy on producing only new growth and foliage. All at the expense of creating additional blooms and tomatoes.

The Best Way To Fertilize Tomato Plants

So how do you know what to fertilize with, and how often to apply it? The answer to those questions is easier (and less expensive) than you might think.

For the last 7 years now, we have settled on a slow and steady method to fertilize our plants. And it has certainly worked wonders in producing a bumper crop year after year.

staking tomatoes - how to best plant tomatoes
Slow and steady fertilizing can help power your plants to a big harvest. Tomato plants benefit greatly from more frequent but less powerful doses of energy. This helps to keep them from growing too fast, and producing more foliage than fruit.

It all centers around using a liquid fertilizing approach. And, applying it in a lower dosage, but on a more regular basis. Not only does it give the plants the nutrients they need, but at a steady, slow rate that allows for strong but regulated growth.

Here is a look at how we fertilize our plants, along with the timing and strength of each dosage:

Why Liquid Fertilizers Work Best – How To Fertilize Tomato Plants Right!

There are certainly a lot of choices for fertilizing tomatoes. From granular mixes, to powders, liquid concentrates and more, the selection can be somewhat mind-boggling. But for us, especially when it comes to fertilizing tomatoes and other vegetable plants, liquid fertilizers are the ideal solution.

We have always been partial to liquid fertilizers for a few very important reasons. For one, nearly all liquid fertilizers can be absorbed in two ways, through the roots, and through the foliage. And that double dose of goodness means plants get the energy they need fast.

For our tomatoes, we rely on the power of liquid compost tea! Not only is it free to make from our own compost, it is filled with the nutrients tomatoes need most.

Even better, however, is that they can be applied as part of your watering routine, giving the plants moisture and nutrients all at the same time.

Selecting The Best Liquid Fertilizer

There are some great all-natural liquid fertilizer options on the market. Some, like Espoma Tomato Liquid Plant Food, are even created with powering tomatoes in mind.

But our liquid fertilizer of choice is and will always be compost tea. Not only is it 100 percent natural and organic, it’s easy to make and apply. In addition, if you have your own compost on hand, it’s completely free to make! (See : How To Make Incredible Homemade Compost Tea)

Compost tea also happens to be filled with the perfect blend of nutrients that help tomato plants thrive. Nutrients that absorb easily, and help to power a crop to a harvest that vegetable gardening dreams are made of!

Listen In To Our Podcast On How To Make Homemade Compost Tea!

But one thing is for sure, whether using a commercial liquid fertilizer or compost tea – fertilizing with a liquid approach is the answer.

All that is left for big success is knowing when to fertilize your tomato plants, how much to use – and for how long to apply it.

When To Fertilize – How To Fertilize Tomato Plants Right!

Along with using the right fertilizer, knowing when to apply it and at what strength are the two final keys to growing a bumper crop of tomatoes.

It is better to provide your plants with regular but less potent dose than just a few large doses. For us, that means using our liquid fertilizer at half strength, and applying it every 10 to 14 days.

For our compost tea, we simply mix one gallon of tea with an additional gallon of water before applying. If using commercial liquid fertilizers, just mix at half of the recommended strength before applying.

Raised Row Garden
As you can tell in the background, the compost tea works wonders in growing healthy and big tomato plants. It also works quite well on pepper plants (in the foreground) to promote healthy roots, sturdy stems, and high producing plants.

This low dosage keeps plants from growing too rapidly. But it also keeps a steady supply of nutrients coming to the plants all the time. Both of which are absolutely huge for growing tomato plants that produce!

How Long Should I Supply My Plants With Fertilizer?

It is important to allow your plants to establish in the soil a bit before fertilizing. For transplants, that means allowing them to adjust for about 10 days in the soil after planting day.

If you happen to grow your plants directly from seed, allow the plants to grow at least 4 to 6 inches high above the ground before starting to fertilize.

Once established, plants should be fertilized every 10 to 14 days for the first 10 to 12 weeks. When using a liquid fertilizer, it is best to do so in the morning hours so the sun’s rays will not burn any foliage.

when to fertilize
Once your tomato plants start to produce larger fruit and it begins to ripen, it is time to stop fertilizing. Fertilizing too late in the season can actually lower yields instead of improving them.

We use about 1/8 of a gallon per plant for small transplants at first. As they continue to grow and develop, we increase the amount per plant to 1/4 – 1/3 of a gallon for each tomato plant.

To apply, use about a third of your dose to water the foliage, and pour the rest around the root zone of each plant. Again, the beauty of liquid fertilizing is the plant will absorb both through its roots in soil, and through foliar action via its leaves.

When To Stop Fertilizing

Once plants reach the point where they begin to fruit heavily and start to ripen the first of the crop, we stop fertilizing. We do this to allow the plant to concentrate it’s energy on fruiting and ripening.

Unfortunately, fertilizing plants later in the year will cause them to use the excess energy to grow more foliage, and not produce more flowers. For most plants, that means stopping all fertilizing after about 12 weeks in the ground.

All in all, our plants receive a total of 5 to 6 doses through the season before we usually stop fertilizing. It has certainly been a formula that has worked like a charm.

Here is to fertilizing your tomato plants this year, and to growing your best crop ever! Happy Gardening, Jim and Mary.

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