Knotweeds are mostly native of the temperate zone in the northern hemisphere, a couple of species occur in tropical regions. Most are fast growing annuals to perennials. Several annual species have a good ornamental value for their showy terminal flower spikes in pure white, brilliant rose or deep lilac colors. Easily grown in any rich, well drained soil with sufficient moisture in summer.
Sow from autumn to late spring in any well drained substrate. Keep soil always slightly moist and pots in a sunny and proteced spot outside. Transplant seedlings as soon as they are strong enough.
All plants are from USDA Climate Zone 6.
20 seeds per package.