There’s no point to growing tall flowers only to have them fall on their pretty faces from wind or the weight of their blooms. Staking after the fact doesn’t work—trust me. Begin staking as soon as plants are about 20 centimetres tall. As they grow, add more ties farther up. Bushier plants such as cosmos, African marigolds and zinnias may need two or three stakes—or use tomato cages. For dahlia tubers, insert two or three sturdy supports at planting time.
I use plastic-coated rebar and bamboo poles between 90 centimetres and 1.5 metres long, and soft, wide ties with which I make a figure eight—the ideal way to secure a slim stem to a stake.