The cultivar Diabolo ninebark (Physocarpus opulifolius ‘Diabolo’) is an aggressive grower. A knowledgeable gardener with a sharp pair of pruners may quickly and easily train Diabolo ninebark into a small tree. Plant a ninebark tree in a large container for multi-seasonal color around your deck or patio. Its common plant name “ninebark” says a lot. […]