How to Grow Cacti in the UK
Have you ever wandered through a garden centre and paused at the cacti section, wondering if these desert dwellers could thrive in our often drizzly British weather? But with the right know-how and a bit of tailored care, cacti can add a striking, low-maintenance flair to any UK home or outdoor space. These resilient plants, known for their sculptural shapes and minimal water requirements, are ideal for busy gardeners or those seeking to create a drought-tolerant display.
In this blog post, we’ll explore some of the best cacti varieties well-suited to the UK climate. Whether you’re eyeing hardy outdoor options or easy indoor growers, there’s something here to spark your green thumb.\
Opuntia humifusa: Eastern Prickly Pear
One of the hardiest cacti for gardens is Opuntia humifusa, often called the eastern prickly pear. This low-growing species forms flat, paddle-shaped pads that can spread up to a metre wide, creating a mat-like ground cover. Its pads are a vibrant green, dotted with clusters of sharp spines and finer glochids (fine, hair-like barbed spines) that give it a fuzzy appearance from afar. In summer, it bursts into cheerful yellow flowers, followed by edible red fruits that attract wildlife, adding a pop of colour and ecological value to your garden.
What makes Opuntia humifusa stand out is its remarkable cold tolerance, as it can survive temperatures as low as -20 ℃ when kept dry. Native to North American regions with variable weather, it adapts well to our milder winters, making it ideal for rockeries or gravel beds where drainage is excellent.
Care Tips:
Plant it in full sun using a gritty, well-draining compost mix to prevent root rot from our frequent rains. Water sparingly during the growing season from spring to autumn, allowing the soil to dry completely between sessions. In winter, protect it from excess moisture by using a cloche or moving potted specimens undercover. Feed lightly with a balanced fertiliser in spring to encourage blooms.
Echinocereus triglochidiatus: Claret Cup Cactus
Echinocereus triglochidiatus, commonly known as the claret cup cactus, is a gem for enthusiasts seeking a splash of drama. This clump-forming plant grows in cylindrical stems up to 30 cm tall, covered in dense spines that range from white to reddish-brown, giving it a textured, almost woolly look. Its crowning glory is the vivid scarlet flowers that emerge in late spring, resembling open cups and drawing pollinators, such as bees, into your garden.
Unique among cacti, its flowers stay open for several days, providing extended visual interest. It’s also highly drought-resistant, storing water in its stems to endure dry spells, which suits our unpredictable summers perfectly. Hardy to around -15 ℃, it’s a top choice for outdoor planting in sheltered spots. This cactus thrives with neglect, making it an ideal choice for beginners.
Care Tips:
Position it in a sunny, south-facing border with well-draining soil enriched by our specialist cactus compost for optimal aeration. Water only when the top few centimetres of soil feel dry, roughly every two weeks in summer, and cease entirely in winter to mimic its natural dormancy. Prune any damaged stems in the spring, and watch for pests like mealybug; treat with a contact insecticide if needed.
Cylindropuntia imbricata: Tree Cholla
For a more architectural presence, turn to Cylindropuntia imbricata, also known as the tree cholla. This upright cactus can reach up to two metres in height over time, with segmented, cylindrical branches armed with long, barbed spines that deter herbivores. Its stems are a bluish-green hue, and in summer, it produces magenta flowers that develop into yellow fruits, offering both ornamental and wildlife benefits.
Its standout feature is rapid growth in suitable conditions, forming a shrub-like structure that’s rare among cacti. It’s frost-hardy to – 20 ℃, provided it’s kept dry, which aligns well with UK gardens that have good airflow and minimal winter wet.
Care Tips:
Plant in full sun using a gritty/sandy compost blend to ensure quick drainage.
Water moderately from April to September, allowing the soil to dry out thoroughly. Avoid watering in cooler months to prevent root rot. If grown in pots, use terracotta for breathability and repot every few years. Mulch with gravel to suppress weeds and retain warmth.
Schlumbergera truncata: Common Winter Cactus
Shifting indoors, Schlumbergera truncata, also known as Christmas cactus, is a favourite for UK homes with its trailing, segmented stems that resemble flattened leaves. These arching branches can extend up to 60 cm, adorned with tubular flowers in shades of pink, red, or white that bloom around the holiday season, bringing cheer to windowsills.
Unlike desert cacti, it’s a forest cactus, an epiphyte from Brazilian rainforests, thriving in humid environments and tolerating lower light levels. This makes it uniquely suited to our often overcast winters, where it can flower profusely with the right cues, like shorter days.
Care Tips:
Place in bright, indirect light, such as an east-facing window, and use a peat-free compost with added perlite for drainage. Water when the top of the compost dries, keeping it moist but not soggy, and mist occasionally to boost humidity. Feed with a tomato fertiliser every fortnight during growth. To encourage blooms, provide cooler nights in autumn.
Disocactus (Epiphyllum) ackermannii: Red Orchid Cactus
Disocactus ackermannii (sometimes still listed under its older name Epiphyllum ackermannii), or the orchid cactus, captivates with its long, strap-like stems that cascade elegantly from hanging baskets. These flat, succulent segments can grow over a metre, bearing large, fragrant white or pink flowers that open at night, releasing a sweet scent that fills the room.
Its epiphytic nature means it absorbs moisture from the air, making it adaptable to indoor humidity without needing constantly moist compost. The nocturnal blooms add a mysterious allure, distinguishing them from daytime-flowering plants.
Care Tips:
Position in dappled light to avoid scorching, and pot in an orchid-like mix with bark and our aerated compost for root health. Water regularly in summer and reduce watering in winter. Ensure good ventilation to prevent fungal issues. Prune after flowering to maintain shape. This cactus rewards patience with spectacular displays, making it a standout addition to any conservatory.
Mammillaria hahniana: Old Lady Cactus
Mammillaria hahniana, commonly known as the old lady cactus, features a globular body up to 15 cm across, wrapped in white, woolly hairs and spines that give it a soft, fuzzy texture. It produces rings of pink flowers in spring, encircling the top like a crown.
Its compact size and woolly covering help retain heat, making it resilient during cooler weather. It’s also prolific at offsetting, creating clusters that naturally fill pots.
Care Tips:
Keep it on a sunny windowsill with cactus-specific compost for sharp drainage. Water sparingly, every three weeks in active growth, and keep dry over winter. Rotate for even growth and inspect for scale insects.
Ferocactus glaucescens: Blue Barrel Cactus
Finally, Ferocactus glaucescens, the blue barrel cactus, features a rounded, ribbed form that can reach up to 50 cm tall, characterised by a powdery blue-green skin and yellow spines. Yellow flowers top it in maturity.
Its barrel shape stores ample water, making it ideal for forgetful gardeners, and it’s hardy enough to thrive indoors with minimal care.
Care Tips:
Plant in gritty compost, water monthly during the summer, and provide bright, indirect light. Protect from frost if outdoors briefly. Robust and eye-catching.
Growing cacti in the UK is more accessible than you might think, thanks to these adaptable varieties. We have created a peat-free cacti compost mix that provides the ideal medium for your cacti to thrive.
This compost is made of thicker and larger coconut fibres to create an optimum balance of nutrition for cacti and succulents. It also has added grit for free drainage and aeration.
If you like to learn more about this product, click here.
