Tomatoes will grow bigger if fed 1 natural garden waste ingredient Monty Don loves using

Tomatoes are a favourite in many gardens due to their ease of cultivation, but they are heavy feeders, requiring more nutrients than other plants. Gardening guru Monty Don suggests that tomatoes will yield larger and tastier fruit if adequately supplied with potassium, an essential nutrient for fruit production.

The gardening expert also revealed how to create a homemade potassium fertiliser to enhance crop growth, using just one common garden plant. Monty explained: "Potassium is what plants need to form good flowers and fruit, and fruiting flowers like tomatoes and gooseberries have quite a high potassium demand. You can boost that at this time of year and improve fruit production. One way of doing that is to go to a garden centre and buy liquid or granular fertiliser, but there's no need as you can also grow your own supply of potassium really easily through comfrey."

Comfrey is a typical garden weed recognised for its large, hairy leaves, which are rich in potassium and other nutrients necessary for tomatoes, such as calcium.

Monty stated: "Its main use to me in this garden is to provide the raw material for a liquid feed that's high in potassium.

"A caution about comfrey is that once it gets established, it has deep roots and it's quite hard to get rid of. However, you shouldn't get rid of too much as it really is so useful."

To make this homemade tomato fertiliser, first, strip the flowers and stems from the comfrey and chop up the foliage before tightly packing the leaves into a waterproof container, followed by topping them with water.

Once the container is brimming, seal it with a lid and pop it somewhere safe in your garden for several weeks to allow the contents to decompose and turn to liquid.

Monty advised: "The idea is to loosely fill a bucket or just put what leaves you've got, then put water in on top of that and leave it to brew for three weeks.

"It's essential to use a lidded vessel for this process and weigh the top down with a stone; while comfrey is beneficial for tomatoes, it emits a horrendous odour as it ferments.

"Then, when it is properly made, it will form a black, vile-smelling sludge, and I'm not exaggerating, it smells disgusting. It's covered not to protect the brew but to protect us from its vile smell."

In about three weeks, check on your concoction, which should have morphed into an unpleasant brown fluid. Transfer this concoction into plastic containers and keep it somewhere cool and shady.

When it's time to feed your tomatoes, strain out the leftover leaves and thin the fertiliser with water at a ratio of one part comfrey to 10 parts water; a darker mix will need more dilution. Next, pour the diluted blend into your watering can and sprinkle it over your tomato plants.

Taking to his blog, Monty also shared a few other natural items he likes to fertilise his plants with - liquid seaweed and compost.

Liquid Seaweed is a 100% natural and organic plant feed and conditioner. It stimulates healthy plants, producing higher yields of crops and more flowers, as well as improving soil conditions.