How to Increase Tomato Fruit Size | 8 Easy Ways

Tomatoes are a great crop to grow at home but if you are sick of small tomatoes then this article is here to help. There are 8 easy ways to increase tomato fruit size at home starting with choosing and preparing the right tomato bed, choosing a fertilizer high in phosphorus and giving them the right amount of light. Regular water is also essential to grow large fruit that does not split.

This article will explore 8 easy ways to increase tomato fruit size at home that are simple to do and will give you large and delicious fruit.

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1. Choose a new space for your tomatoes

To get the best out of your tomatoes choose a new space to plant them in your yard each year. Rotating your tomato patch away from the space they were planted the year before will help to prevent disease spreading from the soil to your plants.

Any underlying disease will lead to smaller tomato fruit size. Avoid this by choosing a new patch each year. Rotating tomato position in a 4 bed system works well. Follow up tomatoes by planting legumes like peas, beans and lupin to repair the soil and add back nitrogen.

2. Plant tomatoes in soil rich in organic matter

Good soil is essential to grow healthy tomato plants and large fruit. Before planting out your new tomato seedlings mix through aged homemade or commercial compost and aged cow manure. Mix this through the top 18 inches of soil to aerate it, add nutrients and help the soil to hold water.

You can add a handful of pelleted chicken manure or a small sprinkle of bone meal to add extra nitrogen to get your tomato plants off to the best start. Growing large, healthy tomato plants with strong roots systems is essential to growing a vine strong enough to hold large fruit.

3. Add a strong stake for support

Larger tomato varieties including Beefsteak, Grosse Lisse and the Burgess Stuffing Tomato are indeterminant tomatoes. They grow a long vine and tomatoes can grow up the vine as it grows. Given the space, some of these tomatoes can grow over 2 meters tall and will need support.

Large tomatoes and vines are heavy so it is best to use a strong hardwood stake to hold them up. Put the stakes in as soon as you plant the seedlings. That way you won’t put the stake through any established tomato roots.

I like to reuse the same stakes each year. Just wash off the excess soil at the end of the season and let them dry in the sun.

4. High phosphorus fertilizer

For the biggest tomato fruit possible feed your tomatoes with a fertilizer that is high in phosphorus. Choose an all purpose fertilizer with a Nitrogen-Phosphorus-Potassium (NPK) ratio of 5-10-5 when the plant starts to produce flowers.

Repeat this again after 6 weeks to keep the tomato flowering and fruiting well. For an easy option use a specialist tomato fertilizer. This will have the correct ratio of nutrients to promote larger tomato fruit size without effort.

Check out tomato fertilizers from Amazon here.

5. Regular water

Regular water is essential to increase tomato fruit size. Dry periods followed by lots of water can cause the fruit to split, which will stop their growth and ruin your fruit.

Tomatoes will need water on most days during the summer period if you live in a dry area. In tropical and sub-tropical areas where there is more summer rain, water tomato plants when the soil surface is dry 2 inches down.

I like to water my tomatoes with a hose so I can give the exact amount of water that each plant needs. Depending on how each plant is positioned, the soil can dry out faster or slower in different areas of your patch.

When I was growing tomatoes in a Mediterranean climate with hot, dry summers, I would water my tomatoes every day, in the morning to keep the fruit growing well.

6. 8 Hours of sunlight

Sunlight is essential to increase tomato fruit size. Long days of warm sun will help the plant to grow large and delicious fruit. Positioning the plant so they get 8 hours of sunlight will give you the best chance of amazing and large fruit.

I grew my largest heirloom tomatoes in a open area that got a full day of sun. This meant that as soon as the sun appear at 6am, all the way until the sun disappeared at 8pm. These long days grew large and delicious fruit that have beautiful natural sugars developed in the skin. The fruit was big and delicious!

7. 3 Inches of mulch

Mulching tomatoes is essential to get the best and biggest tomatoes possible. Surround the plants with 3 inches of straw mulch to help to keep the water in the soil for longer. Mulch will reduce evaporation which will help to keep water consistently available to the plant.

8. Prune the tomatoes regularly

Pruning large, indeterminant varieties is essential to encourage them to produce the largest fruit possible. Allowing the tomatoes to focus their energy on a single vine and the fruit will help the fruit to grow larger.

Remove suckers that grow from the base of the tomato vine as it grows. You can also remove the extra branches that grow from the insides of the leaves up the vine. This will allow the plant to focus its energy on the main stem and the groups of tomatoes growing from it growing them larger.

Pinch out these extra stems growing between the leaf and the main stem to allow the plant to focus its energy on growing large fruit.

Pinching off excess flowers will allow the plant to grow large tomatoes. This means less in quantity but more in quality and size.

How to Increase Tomato Fruit Size | Summary

Tomato fruit size can be increased by giving the plant everything it needs to thrive and focus on fruit development. It starts by growing a large, healthy plant and then helping the plant to focus on fruit growth rather than leaves and stems. Give it the fertilizer it needs and regular water and you will be picking huge tomatoes over summer.

Happy growing.