It would not be late summer without the fresh earthy smell of homegrown tomatoes in gardens, and now is the time when this crop is at its most demanding. 

August is typically a time when tomato plants are nearing the end of their growing season and fruit is ripening to soon be harvested. 

However, as the weather gets hotter in August there is more chance of ripened tomatoes to become cracked, watery or tasteless if gardeners are not maintaining them properly. 

Monty Don from Gardener’s World has shared that keeping tomatoes healthy for the rest of the season can be very easy as long as gardeners do three simple gardening jobs in August. 

On his website, Monty said: “Tomatoes are coming up to their prime harvesting period but to extend this and make sure that all the current green tomatoes fully ripen over the coming month or so there are a few things the tomato grower should do now."

How to get healthy and longer-lasting tomato plants in August

Make sure to regularly prune tomatoes once a week 

Tomato plant foliage usually needs to be cut at this time of year as it can quickly grow and lead to less air circulation around the plant. 

Overgrown leaves, suckers and vines on tomatoes can encourage pests and diseases such as tomato blight, which is very common in summer, which is why it is important to keep on top of pruning. 

If gardeners do not prune their tomatoes it can also lead to the plant spending more energy on foliage rather than fruit production, leading to smaller fruit. 

Monty has shared that pruning can be a very quick task as all you need to do is remove the lower leaves of tomatoes. 

He said: “Strip off the bottom half of the leaves on each plant. This will let in light and air so that the growing fruits get more sun and also the extra ventilation will reduce the risk of disease. 

“This process can be continued weekly until there are no leaves left at all.” 

Be careful not to overwater tomatoes as it will damage the fruit 

Overwatering can dilute the sugars, acids and other compounds in tomato fruit which leads to it becoming watery, mushy and tasteless once it is harvested. 

Watering tomato plants too much can also lead to the skin cracking, which will also affect the flavour but also encourage bacterial growth which can lead to diseases such as root rot and blight. 

To avoid this, gardeners need to water tomato plants consistently but not excessively. Make sure the soil is moist but not waterlogged, and adjust the tomato plant watering schedule based on the weather and temperature.  

Monty said: “Reduce the watering unless it is very hot to avoid the fruit splitting.”

Make sure to fertilise as it will improve fruit production 

Not fertilising tomato plants in summer can lead to there not being enough moisture and nutrients in the soil, which can risk tomatoes splitting open or becoming cracked.

Monty said: “Keep up a weekly feed of liquid seaweed or, if you can make it, homemade comfrey feed. Both are ideal for maximising flower and fruit production.” 

Comfrey is a common weed in gardens which is rich in potassium, which tomatoes need a lot of to grow bigger and juicier fruit. 

In the past, Monty has shared how to make a homemade comfrey fertiliser to give tomatoes a boost and improve their fruit production, but you can also buy granular or seaweed feed at your local gardener centre that be just as effective.