12 most underrated garden flowers you’re not growing yet – including chocolate-scented cosmos

"Airy, almost frothy pink flowers that soften the front of borders and contrast beautifully with more structured perennials, " suggests Mathew.

"It also has many cultivated forms, such as Lychnis flos-cuculi ‘Jenny’, which has fuller, double flowers and a slightly more garden-polished feel, while retaining that same lightness."

Alliums are one of the few ‘add to the list and forget about them’ plants, Matthew explains.

He says: "They require nothing more than being planted and will even take care of their pollinators. They also create movement as their beautiful, large globe flower heads become seed pods that remain all summer and are a great way to add artistic structure to a garden and will be sure to remain in popularity."

Pretty cardinal flowers can be a valuable tool in the garden for adding some personality.

"Though cardinal flowers are often overlooked, they are one of my favourites to bring colour, height and interest to a garden. The flower spikes are bright scarlet, making them a true statement in any flower bed, border, or woodland garden," Lotte explains.

Charlotte explains that the unassuming Red Campion is "ideal for shadier edges, pairing beautifully with ferns, hostas and early summer perennials."

She continues, "There are also cultivated forms like Silene dioica ‘Clifford Moor’, which introduce softer, variegated foliage, allowing it to sit more deliberately within designed planting schemes."

"Common Knapweed is long-flowering, pollinator-rich and surprisingly bold in colour, making it useful among later summer perennials," Charlotte suggests.

"It sits comfortably alongside cultivated cornflowers such as Centaurea Montana and its various blue and purple selections, which bring a slightly larger, more ornamental flower but a very similar character."

While passion flower varieties may already be popular, gardeners are seeing a move away from the traditional English garden towards tropical themes. Expert gardener Lee Furness, advises, "Passiflora, clematis and echinacea to give your garden an exotic feel."

Filed Scabious is a "brilliant bridging plant that threads through planting schemes and works especially well with grasses and roses," Charlotte tells us. "Its close cultivated relative, Knautia macedonica, is already widely used in garden design, offering deeper crimson tones and a longer flowering season while keeping that same airy, informal habit."

"Bougainvillaea gives a simple effect and is fairly low maintenance," Lee explains. Bougainvillaea must be grown in pots to be moved indoors or into a greenhouse during winter, but it makes for a spectacular summer plant.

"The common spotted orchid, too, Dactylorhiza fuchsii, and hardy orchids like slipper orchids, Cypripedium, are great options," Lee adds.

"The Ivy-leaved Toadflax, also known as Kenilworth Ivy, can be found in the wild all around the UK," Lotte explains. "It’s a hardy, low-maintenance perennial that grows rapidly. It features small ivy-shaped leaves and beautiful, delicate blooms in mauve and yellow. It can be grown as a groundcover, but naturally, it loves to climb and makes the perfect addition to a rock garden."

Matthew predicts this unusual flower will be very popular in 2026.

"These versatile bulbs sprout a beautiful mix of purple and white flower petals that appear to grow from the centre of the flower, rather than the tip, hence the name 'nodding bell'," the gardening expert explains. "Its elegant meadow aesthetic is perfect for a naturalistic gardener and can be used in more discreet areas that require something alternative, yet ecologically valuable."