How to Grow Mahonia

Mahonia is a winter flowering, evergreen shrub.

Mahonia can get a bad press because they are sometimes included in landscaping arrangements around supermarkets and roundabouts. Seems harsh, as Mahonia is an easy to grow shrub, with winter colour, and berries for wildlife. On mass, their bright yellow flowers are attractive and some varieties, see below, have scented flowers.

Mahonia is mostly trouble free shrub, and labelled a green wheelbarrow shrub. They look good in a border mixed with other evergreen shrubs and have the advantage of being fast growing. Mahonia is often planted on a perimeter to form a good security hedge because of their very spiky thorns.  

 Mahonia is best in part sun/part shade but is shade tolerant. The winter flowers provide late winter /early spring nectar for any solitary bees emerging from hibernation. Mahonia has attractive evergreen foliage which looks a bit like holly leaves. 

 Planting a Mahonia is easy; soak the root ball in water for 20mins and dig a hole about twice the size of the plant. Place in centre so that the top of the plant in the pot is level with the soil; back fill with good peat free compost firm in and water again.

The most commonly grown type of Mahonia is upright and tall, but in fact there are many varieties with of different sizes, although all tend to be fast growing. There are a number of very attractive scented varities. The group of Mahonia known as M. x media are all upright varieties and illustrated below above center and right is 'Charity' which has lovely yellow fragrant flowers. There is also a low growing variety,   Mahonia repens, which grow up to 30cms, illustrated in the image below and can be planted as ground cover.

The most popular varieties grown in UK gardens are:

Mahonia x media which grows up to 5m high 4 m wide and flowers from late autumn to early winter; good varieties are 'Charity',   'Winter sun' and 'Lionel Fortescue' and all are  sceneted and very hardy H4. These have large upright, yellow, scented flowers. 'Charity' can be grown in a north facing spot, which makes it a good shrub for a difficult growing area.

Mahonia fortunei smaller 1.2m high 1 m wide which flowers in the autumn

Mahonia aquifolium,  known as the Oregon Grape, image left is a smaller compact variety, up to 1.5 metres, very hardy and is spring flowering in March and April followed by blue black berries.

Recently the RHS have awarded Garden Merit (AGM) to Mahonia  x media Underway which reaches up to 3m and has large erect spikes of fragrant yellow flowers in the winter.

Mahonia japonica is also hardy to H4, a mid-sized shrub growing up to 2m and scented.

A recent introduction is a red flowering Mahonia called Mahonia nitens 'Cabaret' which flowers in late summer and autumn.

When growing Mahonia, you do not have to prune the shrub, but a light prune, from time to time after flowering, will trim the shrub into shape and remove any dead branches.

Mahonia are ideal for under planting with snow drops and Hellebores to provide a mixed winter border. Suitable companion shrubs would be Berberis if making a thorny hedge, or Rhododendron, Azalea and Viburnum if planting a mixed shrub border. Another good companion plant is Cornus alba Sibirica with strong red stems.

There is a spineless variety available which has a slender habit, petite growing to around 1 x 1.2. It is fully hardy and looks a little like mimosa and is called M. eurybracteata subs.ganpinensis ' Soft Caress' It is quite different to the traditional Mahonia, and is for sale on Suttons website. Ideal if you would like a compact shrub with winter colour.