Magnolia

Magnolia grandiflora is an evergreen shrub that can grow to a height of 5 metres (16ft) with a spread of 3metres (10ft) and is best grown as a wall shrub.

The off white fragrant flowers appear from July to September.



Cultivation

Week 14: Plant out in well-drained loamy soil in a site sheltered from north east winds and the morning sun.

Plant it in the soil at the same level as it was in its container.

If the plant has become root-bound in the pot gently tease the roots out from the bottom.

Be careful when doing this, because the roots can be quite brittle.

Support the plants with stakes for the first few years.

Week 16: Annually mulch with leaf-mould, peat or compost.

Week 18: Layer suitable laterals and leave for a couple of years to root before severing them from the parent plant.

Week 28: Take 100mm (4”) heel cuttings of half-ripened shoots and insert them in 50-50 gritty mixture of potting compost and grit/perlite.

Place them in a propagator and root them at a temperature of 21°C (70°F).

Once rooted, pot the cuttings up into 70mm (3”) pots of potting compost and grow on in a cold frame for two or three years.

Week 28-30: Generally magnolias do not require pruning however there sometimes comes a time when they outgrow their allotted space and need trimming back.

Branches can become damaged, crossed and in general untidy, and require some attention this is best done when the tree is in full leaf.

Similarly, cut back or remove any outward facing shoots on wall trained evergreen plants.

Pruning at this time allows pruning wounds to heal before the onset of winter, and it also makes them less prone to dieback.

Magnolias can be slow to heal and new growth is often not made until the second season after pruning.

When trimming overgrown plants do not trim back all the branches, it is better to select the highest or widest-growing branches for removal, i.e. the ones that will reduce the overall height and spread and maintain the desired shape.

Keep large cuts into old wood to a minimum on deciduous magnolias.

Week 42: Sow freshly collected seed, in pots containing a 50-50 gritty mixture of potting compost and grit/perlite.

Peel off seed coating prior to sowing and use immediately, this is most important as any remaining coating will inhibit germination.

The seeds must be subjected to a cold period in order to germinate.

This can be done by leaving them outdoors for the frost to get at them, or they can be placed in a fridge for a month.

Germination can take 12-18 months.

When the seedlings are large enough to handle, plant them directly into a nursery bed outdoors, or pot them singly into 70mm (3”) pots of potting compost and grow on in a cold frame for two or three years.





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