• AGM plants

    AGM plants have been through a rigorous trial and assessment programme. They are:

    • Excellent for ordinary use in appropriate conditions
    • Available to buy
    • Of good constitution
    • Essentially stable in form & colour
    • Reasonably resistant to pests & diseases

Of all hardy flowering trees, magnolias, with their large waxy blooms, are perhaps the most spectacular. But as gardens get ever smaller, many of us struggle to fit these delightful plants into our plots. Drive down any suburban street in Britain and the chances are you’ll see a Magnolia × soulangeana hacked into an unhappy blob, displaying none of its natural grace and form. Luckily there is a range of cultivars that can be accommodated into small gardens, with a spread of flowering times. Furthermore, many in this selection are among the least fussy of the magnolias, growing well in gardens up and down the country.

Click to enlarge: Magnolia 'Caerhays Surprise'Spring surprise


Magnolia flowers cannot be ignored, especially in spring when the garden is beginning to stir. The candy-pink blooms of deciduous M. ‘Caerhays Surprise’ AGM start opening at the end of March, before the foliage appears, and last well into May. Each waterlily-shaped flower has 9-12 narrow tepals, with a darker pink tint on the outside. It is small tree that grows slowly to a height of around 4m (13ft) in 10 years.  

Click to enlarge: Magnolia stellata 'Centennial'Small but perfectly formed


Magnolia stellata is one of the best for really small gardens. As the name suggests, it has star-shaped flowers, formed of strap-shaped petals. Plants are bushy and will grow slowly up to about 3m (10ft) tall. The cultivars ‘Centennial’ and ‘Jane Platt’ both have an AGM. The latter is free-flowering with beautiful, soft pink flowers.

Click to enlarge: Magnolia 'Leonard Messel'Petite and perfumed

One of the benefits of a smaller magnolia is being able to get up close and inspect the blooms, especially when they are scented. Profuse-flowering and perfumed M. × loebneri  ‘Leonard Messel’ AGM has delicate light pink flowers which open before the leaves. M. sieboldii ‘Colossus’ AGM is a slow growing shrub with highly fragrant, white flowers up to 15cm (6in) across, borne in late spring and early summer. Its ultimate height and spread is rarely more than 3m (10ft).  

Click to enlarge: Magnolia grandifloraGrandeur on a small scale

If you’re taken with the timeless elegance of Magnolia grandiflora (pictured), M. laevifolia ‘Gail's Favourite’ has been likened to a miniature form. With small, shiny green leaves, its rusty-red, hairy buds open to reveal, small, cup-shaped flowers. As a shrub that only reaches 2m (7ft) in height it is possible to admire the beautiful crown of carpels and stamens in the centre of each bloom.

Click to enlarge: Magnolia liliiflora 'Nigra'Black Beauty


It is no surprise that the deciduous, M. liliiflora ‘Nigra’ AGM is one of the most commonly grown cultivars. Introduced from Japan in 1861, it bears upright, tulip-shaped flowers primarily in June, then sporadically for the rest of the summer. Blooms are almost maroon in colour with an inside of delicate pink veins. It will grow to 3m (10ft) in height, but will only spread 3m (10ft), making it an ideal focal point.

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