Hawaiian Rainbow

Corn

75d to harvest

Feel the first silk-bright glow as the ears emerge—Hawaiian Rainbow corn develops striking, multicolored kernels that shimmer like stained glass in the garden. The kernels are firm and pleasantly crisp, with a vivid spectrum that makes each ear a living centerpiece. Grow it for ornamental impact in beds and borders, and for show-stopping displays of color that shine at harvest and beyond.

Crop Dates

Milestone	Date
Start Indoors	Direct Sow
Last Frost	Apr 1st
Transplant / Sow Outdoors	Apr 1st
Harvest Begins	Jun 15th
Harvest Ends	Nov 5th

Crop Details

Trait	Value
Days to Maturity	75
Sun Requirements	Full Sun
Growth Habit	Upright
Support Needed	None
Planting Depth	Normal
Germination Temp (°F)	55
Min Soil Temp (°F)	55
Min Night Temp (°F)	28
Harden Off (days)	Not Required

Frequently Asked Questions

What pest or disease problem is most common on sweet corn (Zea mays var. saccharata) and how do I treat it?

Corn earworm and fall armyworm are common on sweet corn, with larvae boring into developing ears. Inspect weekly once silks appear, then apply a labeled Bt product (Bacillus thuringiensis) aimed at corn caterpillars as soon as you see fresh feeding or early frass. If you notice smut galls (black, swollen kernels) on ears, remove and discard the affected parts promptly to reduce spread to nearby plants.

How often should I water sweet corn during the main growing phase (after tassel and ear formation)?

During tassel-to-ear-filling, keep the soil consistently moist but not waterlogged, aiming for about 1 to 1.5 inches of water per week depending on heat and rainfall. Water deeply 1–2 times per week so the moisture reaches deeper roots; shallow daily watering often leaves corn drought-stressed at ear depth. Mulch lightly around plants to reduce surface drying, and increase watering if leaves start to fold or turn dull-gray.

How can I tell when Hawaiian Rainbow sweet corn is ready to harvest?

Harvest about 20–25 days after the silks first emerge and when the tassels have begun to dry. Kernels should feel plump and release a milky, whitish liquid when pressed with a fingernail; if the liquid is watery or clear, leave it a few more days. Pick in the morning for the sweetest flavor, and harvest every day or two as ears ripen quickly.