Sunflower 'Mammoth'

Water when top 2 inches of soil are dry. Fertilize once or twice while growing. May require staking.

Position in a full sun location and remember to water moderately. Keep in mind when planting that Mammoth is thought of as half hardy, so remember to protect this plant from frosts and low temperatures. Ideally plant in loamy and clay soil and try to keep the ph of your soil between the range of 5.7 and 8.1 as Mammoth likes to be in weakly acidic soil to weakly alkaline soil.

Try to aim for a seed spacing of at least 3.96 inches (10.16 cm) and sow at a depth of around 0.99 inches (2.54 cm). Soil temperature should be kept higher than 16°C / 61°F to ensure good germination.

By our calculations, you should look at sowing Mammoth about 21 days before your last frost date.

Plant seed outdoors after the last frost when soil temp reaches 60 degrees Fahrenheit. Cultivate and enrich soil with compost. Keep moist until seedlings are established.

Ensure that temperatures are mild and all chance of frost has passed before planting out, as Mammoth is a half hardy plant.

The botanical epithet is from the Latin annuus meaning “annual”.¹

First offered by seed companies in the 1800’s.

Sunflower

¹ Latin Dictionary