Magnolia

Magnolia comes from the subfamily Magnolioideae of the family Magnoliaceae and is a large genus of about 210 flowering plant species, as well as being an ancient genus.

This pretty plant was named after the French botanist Pierre Magnol and is said to have been in existence even before bees joined the earth. In fact, the flowers are said to have been put in place to encourage pollination by beetles.

Creating the perfect home for magnolia

If you wish to grow magnolia yourself, it’s important to prepare the site and conditions. To encourage both growth and flowering, place magnolias in an environment that boasts full sunlight in fertile, moist garden soil.

If you only have dry, alkaline soil to work with, consider using the Magnolia grandiflora variant. On moist, alkaline soils, choose M. kobus, M. seiboldii, M. × loebneri, M. stellata or M. wilsonii. For wet soil, choose M. grandiflora and M. virginiana.

Lighting conditions

An environment that gets the correct amount of sunlight is equally as important as the soil conditions. If your garden area gets only light dappled shade, choose later-flowering deciduous species, such as M. wilsonii and M. sieboldii.

For a sheltered garden, opt for M. grandiflora or M. delavayi, as both of these variants will thrive when placed against a warm, sunny wall and are certainly not suited to windy, cool gardens and cold temperatures. Frosts are renowned for harming these blooms in the spring.

Evergreen magnolias are popular options to grow against a wall and can also be grown in containers.

Pruning and training

Pruning is seldom required when dealing with deciduous magnolias. For best results, follow these handy tips:

• remove poorly placed, weak growth by shaping trees when you plant them and tip back any lengthy shoots
• If you’re too heavy on the pruning, especially when pruning mature magnolias, you can induce watershoots (these are also referred to as lengthy vertical, vigorous shoots) and dieback. With this in mind, routine pruning is often restricted to the removal of deadwood and watershoots.
• When pruning to stunt the size of the plant, try to maintain a balanced and open crown by thinning out stems to a side shoot or the trunk. It’s a good idea to spread out the pruning over several years, as will help to avoid causing stress to the tree.
• Trees can be slow to recover, which is why renovation should be completed over two or three years.
• Avoid unsightly stubs by pruning branches back to a natural fork.
• If pruned in late winter or early spring, the cuts can bleed. Pruning should be therefore completed between mid-summer and early autumn.

Evergreen magnolias

Other than trimming any lengthy, young branches or removing any lower boughs, (only if a bare stem is desired) young trees need no pruning at all.

Hard pruning is only necessary when repair or renovation from storm damage is required. To do this, trim back the main framework of the plant. Again, it is better and safer to spread this work over several years.

Alternatively, you can prune free-standing trees in spring, just as growth begins, and well-trained specimens in the months of summer.

Wall-training

If you’re looking for a magnolia that grows exceptionally well against a sun-drenched wall, look no further than the evergreen Magnolia grandiflora. To wall-train trees, you will need to invest in wires and supports.

You can use these tools to train the plants, by tying shoots at 45 degrees, then lowering them to a horizontal position the following season.

On top of this, you must ensure regular pruning, which involves shortening any outward-growing shoots and removing shoots growing towards the wall.

You may even wish to remove one or two leaves if the plant is looking too heavy. Pruning can be delayed until immediately after the plant blooms, but only if the outward-growing shoots show flower buds.

Propagating

Layering shoots near ground level is the simplest and most hassle-free propagation method in existence. Deciduous magnolias can be grown from both greenwood and soft cuttings. For best results, you should use a liquid feed and add to rooted cuttings. This process should be undertaken to overwinter in a frost-free area.

Magnolias are not the easiest to grow from cuttings, especially when using artificial light. However, if they do survive their first winter, you’ll be left with a healthy, beautiful plant.

For evergreens, use semi-ripe cuttings in the months of late summer and early autumn. Even though you can propagate Magnolias from seed, they can take an impressive ten years to start flowering. For best results, collect seeds just as the cones begin to split.

Because of a lack of pollination, many of the seeds won’t fully develop. If you notice that the shiny black seeds are covered by an orange-red flesh, it’s important to clean this off using water.

Once you’ve done this, mix the seeds with vermiculite or moist sand, then set in a polythene bag. You should store this in the fridge between two and four months before sowing and this should be done undercover. Dried seed is seldom successful.

Prior to planting successful seeds in the garden, pot seedlings as soon as they are big enough to survive in a container, and grow in these pots for two to three years.

Problems

• Newly planted shrubs can take up to several years to establish themselves before they begin to flower, they are however worth the wait. Flowering is also very reliant on where you place the trees. For example, M. Grandiflora planted in warm, sun-drenched areas is likely to thrive. It’s important to note that overly pruning your blooms can delay flowering.
• If you notice blackened flowers or buds, it’s likely your plant has been the victim of frost damage.
• Yellow leaves indicate excessive alkalinity.
• Leaf loss is another problem, as they do tend to shed after several years, which leads to alarming leaf fall in early summer, although this is harmless.
• Look out for signs of bracket fungi, honey fungus, brown leaves, and Phytophthora root rot.

Source: rhs.org.uk