Many herbaceous perennials put on a lot of growth in spring and early summer. This makes them vulnerable to collapse, especially in heavy rain or strong wind. Staking is one answer to this problem. Another one is not letting them get to that stage in the first place by following these simple principles.
1. Go easy on fertilisers, especially high-nitrogen ones that promote growth. Instead, get your soil into good condition using home-made or shop-bought compost, either dug in or as mulch.
2. When planting, remember that sun-lovers will get leggy and weak in the shade. Read the labels and plant accordingly.
3. Give each plant enough space. Sufficient light all around and free air flow produce stronger plants.
4. Water rarely, only if and when necessary, giving your plants a generous deep drink that will help them to grow healthy strong roots and get the plants through any dry spells. As plants can only take water up through their roots, water the soil and not the plants.
5. How about a “Chelsea chop” to prevent the flop? This is the cutting back of stems by one third to a half in late May, at about the time of the Flower Show. Late-flowering, clump forming perennials such as Sedum, golden rod (Solidago), cone flower (Echinacea), sneezeweed (Helenium) respond well. The resulting plants flower a bit later, but are shorter and sturdier.
6. Keep them young and strong. Every few years dig up and divide the clumps, replanting the sections separately into well prepared soil.
However, some plants will need extra support no matter what - giant flowers of some peonies spring to mind. So there are always canes and pea sticks, netting stretched horizontally, or a multitude of manufactured plant supports. Just remember to fit them sooner rather than later!