Hand weeding is the most sustainable way to keep irises and other garden plants healthy. Getting rid of weeds in the spring, when they are tiny, is easier and quicker than waiting until later in the season when they have grown bigger. Plant iris rhizomes so that their tops are exposed. Keeping iris beds free of weeds and other plant growth allows the exposed iris rhizomes to bask in the sun, keeping them healthy.
Do not put plants that have gone to seed on the compost heap. Cut off the seed heads and throw them away. This ensures that you won’t introduce unwanted seeds into your compost that will inevitably sprout in the garden.