Hazel Sillver

During May, the charity Plantlife encourages people not to mow their lawns. As well as attracting and helping wildlife, it's an opportunity to enjoy the sight of flowers blooming in long grass. Observing what appears – from interesting wildflowers (orchids, perhaps) to wildlife (such as grasshoppers) – is fun and, obviously, No Mow saves a lot of time. However, going the whole hog isn't for everyone. Those with children who enjoy careering around the lawn and people who entertain in their gardens won't want to let all their grass grow long. Therefore, a smaller No Mow area is more appealing and something that can be kept up throughout the summer.

Drought-tolerant, laden with nectar, evergreen, long-flowering, and so pungent that it fills the garden with scent, lavender is deservedly popular. The late garden designer Rosemary Verey said, «You can never have too much of it in your garden». In its preferred conditions, of well-drained soil that is baked by the sun, it is easy to grow.

Straddling the seasons, rhododendrons are the buxom queens of spring, leading us into the floriferous summer months without any subtlety. They can grow into vast shrubs that, in bloom, are wondrous clouds of colour formed of handful-sized flowerheads.

The beautiful balcony plants on the terrace at the London house of Henrietta Courtauld of the Land Gardeners

Ivy on the front of James Mackie's cottage

Cotoneasters are not a well-known group of plants, and these excellent berrying shrubs are often unfairly labelled dull. The culprit responsible for this reputation is Cotoneaster horizontalis (wall spray), which sprawls across front gardens and car parks up and down the country, and is, admittedly, rather dull. But, beyond the ubiquitous blandness of C. horizontalis, there are many wonderful cotoneasters that deserve to be more widely grown.

White Christmas Cactus, £11.99 from Hortology

As well as being that haloed place where one can enjoy a bit of peace and quiet and a hot soak, the bathroom is also one of the best rooms to grow house plants. Its high humidity is a haven for a lot of indoor plants because so many of them hail from tropical or subtropical forests. There they flourish in the consistently damp, warm air and the light that pours in between the trees. These plants will feel right at home in bathrooms, shower rooms, and kitchens, if provided with the indirect light and average-to-warm temperature that most of them crave.

It is claimed that some houseplants purify the air of our homes. They are said to rid the indoor environment of pollutants, in turn improving our breathing, our mood, and our overall health. So, is it true, and, if so, how many plants does it take to clean a room?

Dramatic and elegant, amaryllis (Hippeastrum) are bulbous indoor plants that cheer us through the coldest months. The huge flowers bloom atop tall, sturdy stems, opening like colourful trumpets, as if about to blast away the winter blues with a clarion call.

Mahonias are woody evergreen shrubs and the best of them flower in winter. In the past, they were regarded as something to shove in the shady corner or, even more insultingly, as car park plants. But now – thanks to the demand for architectural foliage – they are having their moment in the sun... or, rather, their moment in light shade, which is where they prefer to be.

As inextricable from mass festive wares as tinsel and paper hats, the poinsettia blazes red in most shops and homes during December. Being such an omnipresent sight makes it unappealing for many of us, but, thankfully – if the standard scarlet species makes you wince – there are less common forms available that are well worth buying to brighten the house this Christmas.

Witch Hazel '‘Amanon’ 'at Kalmthout Arboretum in Belgium

Should you be stopped in your tracks by the blazing colour of a tree this autumn, it is likely to be a maple (Acer). Their distinctive palmate leaves burn breathtaking, vivid shades of scarlet, ruby, or gold before they fall, outshining most trees in the vicinity. Some acers also offer colourful spring foliage; others have a sculptural spreading shape with multiple trunks; and a few provide attractive bark during the winter months.

Perhaps the most beautiful of flowering trees, magnolias are adorned with luxurious, flamboyant flowers in spring and summer. These generous blooms are goblet- or saucer-shaped and a handful or more in size.

Cherry blossom on show in a west London garden by Sheila Jack

Cleve West's Centrepoint Garden, which won a gold medal at Chelsea Flower Show

Cosmos bipinnatus ‘Fizzy Pink’'

Blazing in shades of orange, gold, peach, and red, marigolds inject the garden with warmth and cheer during summer and into autumn. The flower name encompasses two types of plant: Calendula and Tagetes. Both are easy to grow from seed and boast the fascinating ability to attract wildlife and, in turn, stave off pests in the vegetable garden.

Helianthus annus ‘Sonja’

Chlorophytum comosum ‘Vittatum’ — available from Hortology

As far removed from an English cottage garden as you can travel, the passion flower (Passiflora) is one of the most theatrical and exotic of plants. The weird and wonderful blooms are embellished with many showy parts that together remind you of peering into a kaleidoscope as a child: in the centre, the anthers, stigmas, and ovary protrude over the filament rays, which are marked with circles of incredible colour.