Lily of the valley (Convallaria majalis) is a small woodland perennial plant which spreads by means of underground stems (rhizomes) into dense mats of flat-bladed foliage. In mid-spring tiny white bell-like blooms fill the air with a distinctive, coyingly sweet scent commonly used in perfumes and toiletries. The impenetrable masses of foliage makes lily of the valley a superb choice to hold back erosion or grow in shady locations where nothing else will grow, but the bane of perennial beds, where they will choke out all other species. Lily of the valley eradication requires persistence and determination.
Mark the outer bounds of your invasive lily of the valley mat using stakes and string. Position the string close to the ground to allow for easier digging around it.
Dig out the mat of lily of the valley within the stake-and-string marked area using the flat-bladed shovel. Transplant the mat to a more desired location, or dispose of it by placing it in the trash, but do not place it in the compost pile.
Wearing gardening gloves, lay the piece of hardware cloth across the wheelbarrow. Use the spading fork to loosen the soil where the lily of the valley mat had been located, to a depth of one foot.
Shovel small amounts of loosened soil onto the hardware cloth. Shake the hardware cloth gently to sift dirt. Remove all remaining pieces of lily of the valley root masses and place them in black plastic garbage bag. Dispose of the bag in the trash when it is full. Return cleaned dirt to the garden area.
Place black plastic sheeting over the area where lily of the valley was growing. Stake it in place with the wooden stakes originally used to mark the area.
Lift the black plastic after six months, or in the next growing season. Dig out any sprouting lily of the valley plants, spading deeply to remove their root masses.
Refill area where lily of the valley was removed with topsoil and compost, and plant as desired.
Paint glysophate weed killer on any lily of the valley plants which emerge in your new plantings using a disposable paint brush, being careful not to get any of the chemical on surrounding plants. Reapply through the growing season at intervals as recommended on the manufacturer's label.
Paint triclopyr ester week killer on any lily of the valley plants which emerge the growing season after using glysophate weed killer, being careful not to get any chemical on surrounding plants. Reapply through the growing season if necessary at intervals as recommended on the manufacturer's label.
Repeat sequence of eradication steps as necessary.