Larkspur
Consolida ajacis
Larkspur is a beloved cottage-garden annual with tall, graceful spires of blue, pink, white, or mauve flowers that bring height and a romantic, wild feel to borders and cutting gardens. It is a cool-season lover that performs best when sown in autumn or very early spring. Sow directly in September–October for strong overwintered plants, or in March–April for a summer display. Choose light, well-drained soil in full sun and space 25cm apart. Plants reach 90–120cm and flower from June to August. All parts are toxic if eaten. Larkspur is outstanding in cut-flower arrangements — harvest when the bottom third of the spike is open and sear stem ends in boiling water for 10 seconds to prolong vase life.
Plan where to grow Larkspur using our vegetable garden planner.
When to Sow Larkspur
Sow larkspur in September, October, March, April.
Time to Harvest Larkspur
Expect to harvest approximately 8 months after sowing.
Companion Plants
Expected Yield
A 1m row provides 15–20 tall cut spikes.
Common Problems with Larkspur
Plants rot in wet winter soil
Larkspur needs sharp drainage. Sow in raised beds or improve heavy soil with grit and coarse sand before sowing.
Tall flower spikes blow over
Plant in a sheltered spot or support with pea sticks. Autumn-sown plants develop stronger roots and stand up better.
Mildew on lower leaves
Ensure good spacing for air flow. Water at the base only and remove affected leaves to stop spread.
Plan your larkspur in the allotment planner
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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.