How to Prune Lupins

Pull off yellowing or dying leaves from lupine plants as they appear to maintain an overall lush green appearance. Regular removal of yellowing leaves also helps to prevent bugs and disease from harming the plants. Garden pruners can be used, but simply plucking dying leaves by hand is the easiest way to remove old leaves.

Prune spent flower spikes from lupine plants as necessary throughout the growing season. Lupine plants will typically grow a single large flower spike with smaller flowers spikes emerging on lower levels of the plant. That will follow the initial bloom of the large spike. Prune the larger flower spikes as they fade to encourage growth of smaller subsequent flower spikes.

Cut the spent flower spikes with garden pruners at the base of the spike and just above the next green leaf that is on the plant stalk. Leave no yellowing leaves and dead or dying flower pods. Prompt removal of spent flower spikes will prevent the plant from putting its energy into seed production and encourage further flower production.

Cut the first flower spike to appear to encourage lupine plants to grow in a bushier more compact form with multiple flower spikes. Natural growth without pruning with typically result in a taller more sparse plant with a single large flower spike and several smaller less significant blooms.

Pull the dead lupine plants out of the ground by hand removing the entire plant following the completion of the blooming cycle. There is no need to wait until the plant fully dies by itself before pulling it out of the ground. After the last flower spike has bloomed and faded, remove the plant. Discard it in a compost pile or green waste garbage can.