Agapanthus
Agapanthus africanus
Agapanthus, or African lily, is a statuesque summer perennial producing bold globes of blue or white trumpet flowers on tall, strap-like stems from July to September. It thrives in the UK given a warm, sunny spot and well-drained soil — it is famously tolerant of drought once established and flowers best when its roots are slightly congested. Plant container-grown specimens in April–May, setting the crown just below the surface. In cold gardens, mulch deeply in autumn or grow in pots that can be moved into a cold greenhouse. Divide congested clumps every 4–5 years in spring for the best flowering. The tall flower heads are excellent in large arrangements.
Plan where to grow Agapanthus using our vegetable garden planner.
When to Sow Agapanthus
Sow agapanthus in March, April, May.
Time to Harvest Agapanthus
Expect to harvest approximately 15 months after sowing.
Companion Plants
Expected Yield
A mature clump produces 10–20 flower stems each summer.
Common Problems with Agapanthus
Lots of leaves but no flowers
Agapanthus flowers best when slightly pot-bound or congested, and in full sun. Divide only every 4–5 years, and do not overfeed with nitrogen.
Foliage dies back in a cold winter
Deciduous types are hardier than evergreen. In cold areas, mulch with straw in autumn or grow in pots moved to a frost-free greenhouse.
Flower stems snap in wind
The tall hollow stems are brittle. Stake with a discreet cane, or plant in a sheltered corner protected from strong winds.
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French Marigold
Tagetes patula
French marigolds are the workhorses of companion planting — their pungent scent confuses pests and their roots release chemicals that suppress soil nematodes. They're particularly effective planted alongside tomatoes, peppers, and brassicas. Beyond pest control, they're genuinely beautiful, producing a non-stop display of orange, yellow, and red blooms from June until the first hard frost. They're among the easiest flowers to grow from seed, germinating quickly and flowering within 8 weeks of sowing. Deadhead regularly to keep the display going. In the allotment context, scatter them generously between vegetable rows — they attract hoverflies whose larvae devour aphids. The flowers are also edible, adding colour to salads.
Daffodil
Narcissus
Daffodils are the quintessential spring flower in Britain, carpeting woodland edges, roadside verges, and garden borders with golden yellow from February to April. They're incredibly easy to grow — plant bulbs in autumn, pointed end up, and they'll flower reliably for years with almost no care. They naturalise brilliantly in grass, creating meadow-like drifts that improve year on year. The key rule is never to cut back the foliage after flowering until it has yellowed naturally (at least six weeks) — the leaves are photosynthesising to recharge the bulb for next year's flowers. 'King Alfred' types give large trumpet flowers; 'Tête-à-Tête' is a compact miniature perfect for pots and borders. Daffodils are toxic to rodents and deer, so they're left alone where other bulbs get dug up. They're also poisonous to cats and dogs, so take care in gardens with pets.
Sunflower
Helianthus annuus
Sunflowers are the flowers that children grow and adults never tire of — their cheerful, towering presence lifts any garden. Giant varieties like 'Russian Giant' can reach 3 metres or more, turning any allotment into a dramatic backdrop. For cut flowers, try multi-headed varieties like 'Velvet Queen' (deep burgundy) or 'Lemon Queen' (pale yellow). Sow seeds directly where they're to grow from late April — they germinate quickly and grow at an astonishing rate. In exposed positions, stake tall varieties to prevent wind damage. The seed heads provide valuable food for goldfinches and other birds in autumn — leave them standing rather than cutting them down. Sunflowers also have practical uses on the allotment: they can act as living supports for climbing beans, their deep roots improve soil structure, and they attract pollinators to your plot. Slugs can destroy seedlings, so protect them until they're large enough to withstand nibbling.
Sweet Pea
Lathyrus odoratus
Sweet peas are the quintessential English cottage garden flower, grown primarily for their intoxicating scent and delicate, ruffled blooms. They're climbers, reaching 1.5–2 metres, and need support — wigwams of canes, trellis, or netting all work well. The golden rule is to pick, pick, pick: the more you cut, the more flowers the plant produces. Once you let seed pods develop, flowering slows dramatically. For the longest season, sow seeds in October in root trainers and overwinter in a cold frame — these autumn-sown plants flower weeks earlier than spring sowings. Alternatively, sow in March–April under cover. Nick or soak the seeds overnight before sowing to speed up germination of their hard seed coats. 'Matucana' has arguably the strongest scent; 'Spencer' types offer the largest, most ruffled blooms. Sweet peas make sublime cut flowers, filling a room with fragrance for days.