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Coffee Grounds & Tomato Plants – 3 Ways To Use Coffee Grounds To Grow Great Tomatoes!

Looking for the easiest and best ways to use coffee grounds to power your tomato plants to a bigger and better harvest than ever this year? 

Coffee grounds have all kinds of uses when it comes to improving soil and helping plants grow. From fertilizing houseplants to heating up compost piles, powering potting soil and more, there seems to be no limit to what the leftover grounds from a cup or pot of coffee can do for a gardener.

But as beneficial as spent grounds can be for all of the above situations, it’s perhaps with the beloved tomato plant where they truly take their powers to the next level. And not just with young tomato plants, but at nearly all points of a tomato plant’s lifecycle – from helping a tiny sprouting seed, to aiding a fully mature adult plant loaded with ripening tomatoes!

coffee grounds and tomato plants
Coffee grounds can help tomato seeds germinate faster – and allow mature plants to produce more blooms and tomatoes!

How Coffee Grounds Help Tomato Plants

So why are coffee grounds so special for tomato plants? And how exactly do they help them grow better from start to finish? As it turns out, leftover grounds have two key attributes that are extremely beneficial for both tomato seedlings and adult tomato plants.

The first is that once run through the coffee making process, the grounds left behind contain 3 essential nutrients that tomato plants love – nitrogen, phosphorous and potassium. Even better, those nutrients happen to be in a form that when used in the soil around plants, they can absorb quickly into the roots of a tomato plant.

Coffee Grounds & Moisture

But the benefits of coffee grounds don’t stop with just giving tomato plants great energy. Spent coffee grounds also have the ability to retain a tremendous amount of moisture. And if there is one thing tomato plants need to survive and thrive – it’s water!

Tomato seeds need water to swell and sprout. Likewise, they need even more moisture to grow into tiny seedlings and spread roots under the soil. But the need for water continues as a tomato plant grows beyond a seedling. First, it needs water to grow healthy stems, roots and foliage. And finally, water is once again needed to form the plant’s fruit.

Proper moisture is critical for tomato plants. And when coffee grounds are used in the soil around plants, they can help keep that valuable moisture around and available for roots. This is especially helpful as young seedlings develop.

Believe it or not – tomatoes are made up of 95% water. And if there isn’t enough moisture in the soil to absorb into the plant – your plant and your harvest will suffer. The good news? As you will see below, coffee grounds can more than help with that issue!

Perhaps the best part of all for using coffee grounds is that you can get them for free. All by simply saving your leftover grounds each morning. And are they ever easy to save to use later. See our article: 2 Easy Ways To Save Coffee Grounds In Winter – Without Molding.

Now let’s take a look at three great ways to use all of those leftover coffee grounds (and coffee too) to help your tomato plants grow better than ever this year!

Coffee Grounds & Tomato Plants – 3 Great Ways To Power Tomato Plants With Grounds!

Using Coffee Grounds When Starting Seeds

Coffee grounds can be tremendously helpful when starting seeds indoors. Especially when it comes to getting tomato seeds to germinate. And they are equally adept at helping young seedlings to develop strong roots and stems as well.

Mixing in a few tablespoons of spent coffee grounds into your seed starting soil is all it takes! The grounds help to hold moisture in around the seed, allowing it sprout quickly. But even better, the trace amounts of nitrogen, phosphorous and potassium power up tiny seedlings fast!

Listen In Below To Our Podcast On How To Use Coffee Grounds & Egg Shells All Over Your Garden!

When mixing in coffee grounds with seed starting soil, mix two tablespoons for every 3 cups of seed starting soil. Your seeds and seedlings will thank you!

Using Coffee Grounds When Planting – Coffee Grounds & Tomato Plants

Coffee grounds can really help power young transplants on planting day! Once again, it’s that double combination of energy and water retention that are perfect for helping young plants establish outdoors.

When planting, mix in three to four tablespoons of coffee grounds into the soil in each planting hole. The grounds will blend with the soil to help it absorb and hold more moisture around the roots. At the same time, they will slowly release all of their nutrients to power strong, early root growth.

If you really want to load up on the power of grounds, finish by adding a few more tablespoons on top of the surface of each plant after planting. Every time it rains or you water, the nutrients will leach out of the grounds. And when they do, they go down into the roots of your tomato plants, continuing to power them in the process.

The practice of top dressing with grounds is actually great to use all season long. Every two to three weeks, simply spread out a few more tablespoons of grounds around the base of each tomato plant. It will give a continuous low-and-slow feeding to your plants, which can serve as a great boost to regular fertilizing.

A few tablespoons of spent grounds in each planting hole will help power plants – and keep valuable moisture near the roots.

Perhaps best of all, as the grounds break down and absorb into the soil over time, they add valuable structure and humus. With each succeeding garden season, you are left with richer, healthier soil.

Using Coffee Grounds (And Leftover Coffee) As A Fertilizing Tea – Coffee Grounds & Tomato Plants

Perhaps one of the easiest of all ways to use your spent coffee grounds, or even leftover coffee for that matter, is as a fertilizing tea on your tomato plants all spring and summer long. Just as the grounds contain nitrogen, phosphorous, potassium and other helpful trace nutrients, so does the water that runs through the grounds.

After brewing your morning coffee, simply run another pot of water through your spent grounds in the coffee maker. The weak coffee, once cool, makes for a great liquid fertilizers for plants.

Likewise, if you are left with some leftover morning coffee, add an equal amount of water to dilute, and water away. The liquid will give a trace boost of nutrients to your plants. Even better, it will help water them at the same time!

Here is to using coffee grounds to help grow your best tomato plants ever this year. Not only are they incredibly powerful and all natural – they also happen to be free!

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This Is My Garden is a garden website created by gardeners, for gardeners. Jim and Mary Competti have been writing gardening, DIY and recipe articles and books and speaking for over 15 years from their 46 acre Ohio farm. They publish three articles every week, 52 weeks a year. Sign up today to follow via email, or follow along!