Zea mays

RHS Plant Profile
sweet corn

Other common names

corn, Guinea wheat, Indian corn, maize, mealies, ornamental maize, Turkey wheat

Annual Biennial

Sweetcorn is relatively easy to grow and without a doubt tastes so much better that shop bought. There's a great range of varieties to grow, both heritage and modern, and something to suit most gardens and the shorter British summers. If you are short on space you could also try growing baby corn. Sweetcorn is generally classified into three groups. 'Normal' which is the original type of sweetcorn and seeds tend to have the most vigour - they're not as sweet as some of the newer varieties and should be eaten as soon as picked to avoid the sugar being converted to starch. 'Supersweet' which, as the name suggests, have a high sugar content but are not so easy to germinate. 'Supersweet' varieties should not be grown with other varieties as cross-pollination can result in a reduction in sugar content. 'Tendersweet' which are both tender and sweet (although not as sweet as 'supersweet') and can be grown alongside other varieties.

Position

Full sun

Soil Types

Chalk, Clay, Loam, Sand

Max Height

1.5-2.5 metres

Max Spread

0.5-1 metres

Size

Time to Maturity
1 year
Max Spread
0.5-1 metres
Max Height
1.5-2.5 metres

Growing Conditions

Chalk Clay Loam Sand
Moisture
Moist but well–drained
pH
Acid or Neutral

Position

Full sun
Aspect
East–facing or West–facing or South–facing
Exposure
Sheltered
Hardiness
H2

Colour & Scent

Season Stem Flower Foliage Fruit
Spring
Summer
Autumn
Winter

Botanical Details

Family
Poaceae
Native to GB/Ireland
No
Foliage
Deciduous
Habit
Columnar upright
Genus
A genus of five, large, flowering plants the grass family. The most important species, Zea mays is widely cultivated food crop. Male flowers are borne in large, terminal inflorescences (tassels) and female flowers are hidden in clusters in the leaf axils
Name Status
Correct

How to Grow

Cultivation

Grow in a sunny, sheltered spot in soil that has been enriched with well-rotted organic matter. Sweetcorn can tolerate many soil types but prefers well-drained soils with a pH between 5.5 and 7.0. Harvest from July to October. See sweetcorn cultivation for futher information.

Propagation

Sow seeds undercover from mid-spring in pots or modules and then plant out May - June after hardening off and the last of the frosts have passed. Alternatively sow 'in situ' from late spring to early summer. Always plant in a grid pattern to ensure pollination. See sowing vegetable seeds

Pruning

No pruning required.

Pests

May be susceptible to damage from birds, slugs, mice and badgers.

Diseases

May be susceptible to smuts which apppear as large galls on the cobs and stalks in hot weather.