This is why your nasturtiums are not flowering, according to Monty Don

A large pot of nasturtiums is a fabulous way to bring some vivid color to a sunny spot in your garden. The hardy annuals flower all through summer and into autumn, and are generally low-maintenance. 

If you're still waiting for a glorious display of trumpet-like blooms, it's likely due to the condition of your soil, says BBC's Gardener's World host Monty Don.

See: Flower bed ideas – beautiful ways to create floral displays in your garden

During a recent episode of the show, Monty Don begins the pleasant task of filling four large pots at the center of his Jewel Garden. Using rich compost, he pots a mixture of plants which will eventually make for a colorful focal point.

'We've got extra rich compost, which is ideal for the Ginger Lily, and the Bidens will be fine. But nasturtiums flower best in very poor soil,' Monty comments.

'If you put them in rich soil, you will have more foliage than flowers,' he says. We tend to assume that plants need rich, fed soil to thrive, but, as Monty points out, this is not the case for nasturtiums.

See: How to grow nasturtium – an expert guide

Fertile soil with a mix of compost and leaf mold will typically lead to lots of leaves at the expense of flowers. But this can be remedied quickly and easily, by repotting nasturtiums in some poor quality soil. 

Try using some less nutrient-rich soil from your garden, or you could add some grit or sand to your compost to thin the soil out. This will encourage flowering, and the more flowers, the more likely bees will be attracted to your garden. 

If welcoming pollinators, insects and birds to your plot is one of your gardening goals, our wildlife garden ideas will provide lots of inspiration.

There's no doubting that the cheerful blooms of a nasturtium create a spectacular display. They're perfect if you're looking for front yard cottage garden ideas, with their eyecatching color and more 'wild' appearance compared to delphiniums, lupins and hollyhocks.

See: Edible flowers are this summer's biggest gardening trend – and these are the top 5 to grow

However, all is not lost if your nasturtiums aren't blooming, because there's much to appreciate about the leaves. Their delicate, circular forms create a calming contrast against the many geometric shapes found in a garden border.