March is the best time to prune the Butterfly Bush, or Buddleja davidii. Cutting through thick, old stems might seem daunting, but this hardy shrub actually benefits from strong pruning. Since it only blooms on new growth from the current season, pruning hard now, as the sap rises and the first green buds appear, is the best way to ensure lots of flowers in summer.

Timing matters this month. If you live in the south or in a sheltered city area, prune in early March. In colder or more exposed northern areas, wait until mid or late March. This short delay helps protect the new shoots from any late frosts.

Pruning should be dictated by the plant’s specific location within your landscape. If your Buddleja is a standalone specimen in an open space, cut it down to around a foot from the ground. This keeps the shrub compact and allows flowers to bloom at head height. Conversely, if it is nestled within a  garden border, leave a structural framework about two or three feet high. This “head start” allows the new shoots to quickly scale above neighbouring plants.

Beyond aesthetics, this offers a fantastic opportunity to support garden biodiversity during the spring. Instead of discarding the pruned material in the garden waste bin, consider snipping the pruned stems into uniform lengths and bundling them together. They can then be placed in a quiet, out-of-the-way corner, creating a natural “insect hotel.” This provides vital shelter for emerging pollinators and beneficial bugs, turning your routine garden maintenance into a significant win for local wildlife.