Crop type: Sweetcorn
Zea mays Mirai Picnic (‘Mirai 003Y’) AGM
Common name: Sweet corn ‘Mirai Picnic’
Crop slug: sweetcorn
This Allotment Pro editorial draft summarises the cited RHS cultivar profile. Check the source and adjust cultivation decisions for local conditions.RHS cultivar profile
1 - Overview
‘Mirai Picnic’ is an early supersweet sweetcorn producing compact cobs about 15cm long. The shorter cobs are packed with exceptionally sweet, juicy kernels and are usually filled well to the tip. Each vigorous plant commonly produces at least two cobs, so the cultivar combines picnic-sized portions with a useful yield.
The cultivar can perform in poorer soil conditions, although a fertile, moisture-retentive and well-drained site still supports the best growth. RHS timings place sowing in April or May, planting outside in May and harvesting from August into September.
2 - Size
- Ultimate height
- 1.5–2.5 metres
- Ultimate spread
- 0.5–1 metre
- Time to ultimate size
- 1 year
Its vigorous upright stems carry at least two well-filled cobs in a typical season. Allow enough room for a compact pollination block rather than growing plants in a single row.
3 - Growing conditions
- Suitable soils
- Chalk, clay, loam or sand
- Moisture
- Moist but well drained
- Soil pH
- Acid, neutral or alkaline
Enrich the ground with well-rotted organic matter before planting. Although this variety is suggested for poorer soils, steady moisture and good drainage remain important while its kernels and 15cm cobs are swelling.
4 - Position and hardiness
- Light
- Full sun
- Aspect
- East-, south- or west-facing
- Exposure
- Sheltered
- Hardiness
- H2 — tolerant of low temperatures but not freezing, approximately 1–5°C
Plant outside only after frost and choose a warm, sheltered position. The H2 rating reflects a tender annual crop that grows outdoors during the frost-free season rather than surviving winter.
5 - Colour and seasonal interest
| Season | Flowers | Foliage | Fruit |
|---|---|---|---|
| Spring | — | Green | — |
| Summer | — | Green | Sweet, juicy kernels developing in compact cobs |
| Autumn | — | — | Mature 15cm cobs into September |
| Winter | — | — | — |
The profile records green foliage in spring and summer. The edible distinction is the compact, well-filled cob with very sweet juicy kernels rather than an ornamental colour feature.
6 - Botanical details
- Family
- Poaceae
- Native to Great Britain and Ireland
- No
- Foliage
- Deciduous
- Habit
- Columnar and upright
- Name status
- Trade
Genus
Zea is a small genus of large flowering grasses. In sweetcorn, terminal male tassels release pollen while the female flowers and developing cobs sit in the leaf axils, which is why block planting improves kernel set.
7 - How to grow
Cultivation
Grow in full sun in a sheltered site enriched with well-rotted organic matter. Sweetcorn accepts several soil types but prefers well-drained ground around pH 5.5–7.0. Because ‘Mirai Picnic’ is supersweet, separate it from other sweetcorn types if cross-pollination would reduce cob sweetness, and follow the seed packet closely for sowing depth and temperature. Harvest mature cobs from late summer.
Propagation
Sow seed under cover from mid-spring in pots or modules, harden plants off and transplant in May or June after the last frost. Alternatively direct-sow from late spring to early summer. Arrange plants in a grid so wind-borne pollen can reach the silks effectively.
Pruning
No pruning is required.
Pests
Birds, slugs, mice and badgers may damage seed, seedlings or cobs.
Diseases
Smut may produce large galls on cobs and stalks during hot weather.