Cultivation Of Magnolias

Magnolias are very easy to grow. They need no particularly special treatment when planted and thereafter. Except for judicious pruning, and regular fertilizing, they are virtually carefree. Pests and diseases are relatively few. The only downside is that they can be expensive to purchase. Little, if anything, surpasses the exquisite beauty of a magnolia bud, except the flower that follows.

Siting

Before planting anything, it is necessary to study the site that you think might suit. Magnolias like sun, so make sure they will get this benefit at least a good part of each day. Only the very large-leafed magnolias, such as Magnolia macrophylla need part-shade. Most plants do not like strong winds, so avoid this curse, but other than this magnolias are not particular. If your garden is sloping you are fortunate indeed, because magnolias may be planted on the slopes so that you look down upon them.

Planting

Magnolias like best to be planted in good, free draining, preferably acidic (pH 5.0 to 6.5) soil that does not dry out, and they enjoy a sunny situation. However, Magnolia kobus, M. x loebneri, M. seiboldii, M. stellata and M. wilsonii can grow in moist, alkaline soils and M. delavayi and M. grandiflora will tolerate dry, alkaline soils.

As they like plenty of organic material in the soil, it is sensible to make a very good job of preparing the soil and site. Ensure that you dig a hole much larger than the root ball of the tree and add generous amounts of well-rotted manure and compost to enrich the soil. If your soil is dry, consider adding water-retaining crystals when you plant. These will expand to hold water when you water the tree after planting and give the roots a prolonged source of moisture to help them get established. It is not that magnolias are so fussy, it's just that you will be rewarded in proportion to the amount of effort you have expended. If you carefully prepare the site, your magnolia will grow more vigorously and therefore flower sooner. If the soil is poor, then your magnolia will look stick-like and grow but little a year. Eventually, however, it will flower.

Place your magnolia in the prepared hole, which should be about three times the width of the root ball, being very careful to 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 (and magnolia roots tend to girdle, that is, circle the trunk or root ball), gently tease the roots out from the bottom. Be careful doing this, because the roots are quite brittle. You can also cut any circling roots, especially if they are at the top of the root ball or close to the trunk.

Make sure that the tree is firmly in the ground without actually stomping hard on it, and water well.  Mulching is important for your magnolia. This is for more than one reason, the most important being to prevent the plant drying out. Depending upon what you use as mulch, and you have a wide choice, it can also provide nutrients. Suitable mulches are pea vine or barley straw, bark, mushroom compost, leaf mold or compost. If your plant is large, do stake it, because wind-rock can inhibit growth badly or kill the plant outright.

After-care

Having planted your magnolia, the after-care is not at all difficult. As magnolias are surface-rooting, do not use a fork vigorously or wield a mighty hoe, but do give them something to eat. Slow-release fertilizers are simple and good, and of course compost is wonderful. For the first year, it is necessary to make sure the plant does not dry out, but if you have mulched, the need for watering will be much reduced.

It is generally accepted that in these days of container plants you can plant them out at any time. Fall is a good time to plant, for the soil is still warm enough to stimulate root growth. However, many magnolias are field-grown and therefore would not be lifted until early winter, so the plant you buy in the fall would be a holdover, perhaps getting very pot-bound. For this reason spring is the very best option. Having planted, watered and mulched it, your magnolia can then be left to get on with growing without needing further attention for a while.

Coping with frost

Whatever your climate, you may, in some years, experience late frosts, which can damage some flowers. Usually this affects only those species or cultivars that flower relatively early. The climate is unfortunately too variable to accurately predict the arrival of frosts in every year, so if you wish to grow the best of the Asiatic magnolias you are likely to have some years where frost damage will occur.

There are some magnolias that shrug off frosts, e.g., Magnolia stellata and varieties and M. x loebneri and varieties, and so are ideal for those who live in areas where late frosts regularly occur. The other option is to choose magnolias that flower later in the season when frost danger is very low.

Pruning

There are two schools of thought about pruning: one for pruning, one against-and wouldn't there be. If you are able to plant your magnolia with plenty of space around it, nothing looks better than a magnolia with its lower branches intact, so that the tree is clothed from head to foot.

If you have to consider space, firstly keep the tree to one stem, where the variety allows. Then when the tree has grown, remove the lower branches up to a height of about 3 ft (1 m) or so. Pruning will not hurt the tree, but just watch for what are called water shoots (coming from where you cut) and simply remove them. When it comes to species like Magnolia stellata and its hybrids, which are naturally very bushy, it might be sacrilegious to suggest that you remove the lower branches so that you have a little tree rather than a shrub.

There are other reasons for pruning. Sometimes trees put up double leaders-that is, two leading or top growths. One will tend to be weaker than the other, so remove it, otherwise when the tree is older, a strong wind could break one leader. If the tree has branches that cross, they can rub together and cause damage and poor growth, so cut one out. Do this after spring flowering, pruning branches flush with the trunk. Also, be aware that magnolia branches are brittle and can break in ice storms, which is another good reason to prune weaker and damaged branches early.

Fertilizer

Magnolias in the wild grow in forested areas with lots of leaf mold for food. As we already mulched when planting, it will only be necessary to apply some slow-release fertilizer each year, in the spring and the fall. If planted in a field situation, magnolias do not care for uncut grass growing around their trunks, so, if you can, mow around them or spray to prevent grass growth. In the garden, where your tree is probably under planted, weed control needs to be different. As magnolias have roots very close to the surface, do not hoe, but remove weeds by some more gentle method, such as by hand.

COMMENTS

Back To Top