Yes, but go light. Cutting back arum lily means tidying, not a hard prune. You should remove the faded flowers and yellowing leaves, and that is about all the plant asks of you. There is no need to chop it to the ground or shape it like a hedge, so don't reach for the shears with a heavy hand. A few minutes of cleanup a few times a year keeps it healthy and stops it from taking over the bed. Think of the job as light upkeep rather than a big yearly cutback.
Watch the plant instead of the calendar. The white spathes fade to a dull green once the flower is spent, and that color change is your cue. Old leaves turn yellow and flop as autumn sets in. These are the natural signs to step in, not a fixed pruning date. Make sure you check the plant every week or two through the growing season so nothing gets out of hand. When you see those signs, grab your gloves and a clean pair of snips and get to work.
Deadheading arum lily does more than make it look neat. Once a bloom fades, the plant pours energy into making seed inside that green pod. Cut the spent stem and you redirect that energy back into the roots and next year's flowers. The bigger reason is spread. Those seeds drop, sprout, and the plant can self-seed into a thick clump that crowds out everything near it. You should avoid letting seed pods ripen if your garden sits near a stream or damp ground. In some warm, wet places this plant is a known weed. So use a careful eye and snip the pods off early.
Foliage cleanup matters too. Arum lily pruning here just means pulling or cutting away the yellow, mushy leaves as they die back in autumn. Dead foliage left lying on the crown gives slugs, snails, and aphids a damp place to hide and breed. A clear crown dries faster after rain and keeps rot and fungus from taking hold over winter. Don't strip off green, healthy leaves, though, since the plant still needs them to feed the roots. Only take the ones that have already turned yellow or brown.
Safety comes first every single time you cut. Every part of an arum lily holds calcium oxalate crystals, and the sap is a real skin and eye irritant. Bare hands can end up red, itchy, and stinging, and rubbing your eye after handling the sap is far worse. So you should wear gloves whenever you cut or divide the plant, and keep your hands away from your face until you have washed them. Make sure you keep the trimmings away from pets and kids as well, since the plant is toxic if eaten. A simple pair of waterproof gardening gloves is all you need to stay safe.
- Gloves on: Put on waterproof gloves before you touch the plant, every time, to keep the irritant sap off your skin.
- Spent flowers: Cut faded flower stems near the base once the spathe turns green, before seed pods form.
- Yellow leaves: Remove leaves as they yellow and die back in autumn, snipping or pulling them off at the crown.
- Bag the waste: Bin or bag prunings and seed heads rather than composting them, so seeds cannot spread to new ground.
- Wash your hands and tools well once you finish, and store snips clean for next time.
Stick with this light routine and your plant stays tidy without any drastic work. Skip the spring chop that some people give it, since arum lily does not need shaping. Just deadhead through the flowering season and clear the dead leaves each autumn. Do that, keep the gloves on, and bag the seed heads, and you get strong flowers next year with no risk of it running wild in your garden.
Read the full article: Arum Lily: Complete Care and Safety Guide
