The main value of magnolia trees is the amazing flowers. However, quite often there is a problem with the lack of blooming, and that is what this article is about.
The lack of minerals in the soil is one of the main reasons why a magnolia tree does not flower. Inadequate soil, lack of light, and frost damage can also result in a magnolia not blooming.
Read on to learn more about all the possible causes of no blooms and how to fix them.
Too cold climate
Climate plays an important role in the life of all plants. If we talk about magnolia, it is not as frost-resistant as, for example, conifers.
In general, magnolias can be grown in 6 to 9 zones. But there are different types of magnolia that are differently related to the cold climate.
Some nurseries sell magnolias that can be grown in zones 5 and even 4. Indeed, some species and varieties can survive the winter in this climate but may not bloom.
Trees simply will not have enough daylight hours to bloom and will have to use all their energy to survive the winter.
How to fix
Before buying a magnolia, do your research to see if it can bloom in your climate. Choose only a variety that can produce blooms.
Fertilize the magnolia with slow-release pellets in the second half of the year. This can give the tree a boost of blooms.
Protect the magnolia from winter draughts and mulch the root zone to prevent the roots from freezing hard.
A second possible cause of flowering deficiency is inadequate soil. Magnolia prefers well-drained, moist, and nutritious soil with a pH of 5.5-7.0.
If the soil holds water for too long, the tree may suffer from root rot. As a result, it will not be able to flower abundantly.
The soil can also be too alkaline or too acidic. This makes it impossible for the tree to use some minerals and flowering is out of the question.
How to fix
If the ground around the magnolia is constantly wet because of its proximity to water sources, get the water any way possible away from the tree. Next spring, transplant it to a less wet location.
Check the pH of your soil using commercially available soil testing kits. If it is above 7.0, use a soil acidifier to lower it. If the pH is below 5.5, use garden lime to raise it.
Both a lack and an excess of nutrients can cause a magnolia not to bloom.
If there is a lack of fertilizer, the tree will not have enough vigor to produce many flowers. Usually, in yards, the soil is clayey and poor, leading to problems with the trees.
At the same time, if you fertilize with too much nitrogen, the tree will produce a large number of leaves and increase in size. In this case, there can be no or very few flowers.
How to fix
Fertilize the magnolia tree once a year in early spring. Use a slow-release fertilizer. Make sure it contains a nitrogen number no greater than 15.
Avoid fertilizing the tree with only nitrogen fertilizer. Do not fertilize more than once a year and no later than the first half of the year. Never exceed the rate recommended by the manufacturer.
The tree is too young
The age of the tree directly affects the ability to bloom. If, for example, your magnolia is grown from seed, it needs at least 10 years to flower.
On the other hand, trees propagated by cuttings or grafting will flower much earlier. However, you should not expect it to bloom the second year after propagation.
Four to five years is the minimum time after which a magnolia can flower. There are exceptions to every rule, though.
The second factor to consider is the time it takes for the magnolia to take root in its new location. Even if you buy a magnolia over 5 years old, you should not expect it to bloom the second year after planting. It may take 2-3 years for the tree to develop a strong root system and then bloom.
How to fix
If you want your magnolia to bloom faster, buy at least a 5-year-old tree at least 3 feet tall.
Plant it properly and give it proper care. Read more about this in How to Care for Magnolia Trees?
Lack of sunlight
Magnolias need direct sunlight for normal development and abundant flowering. If there is not enough light, the tree will suffer.
On the other hand, some magnolia species need partial shade. If such a magnolia is planted in a place with direct sun all day long, it may suffer from sunburn.
How to fix
In general, each magnolia needs at least 6 hours of direct sunlight per day. If your magnolia doesn’t get enough direct sun, transplant it to a sunnier location or clear the space around it to increase the number of sun hours.
Check with your supplier about how much light your magnolia needs. Provide it with the right amount of sun.
Fertilize the magnolia with a little more fertilizer than usual. This will partially make up for the lack of energy and maybe it will bloom next year.
Late frosts that occur in spring can damage flower buds. This usually happens when the tree is already active and about to bloom. If there is a frost at this time, the flowers will die before they even open.
The second case is when the flower buds are damaged in winter when they are dormant. This happens because of strong frosty winds. The result is the same as in the previous case – no flowers.
How to fix
Plant the magnolia in a place that is protected from winter winds. You can also plant a tree on the north side of the magnolia and this will protect the magnolia a bit.
If the magnolia has suffered from spring frosts, there is nothing you can do. Remove the dead buds and accept that there will be no flowering this year.
Next year, you can cover the magnolia with a frost blanket if frosts are predicted in the spring. However, this is not an easy task. Besides, late frosts don’t happen every year.
If you haven’t bought a magnolia yet, prefer a late-blooming variety. Such varieties usually bloom when there is no risk of a late frost.
If you prune a magnolia at the wrong time, new flower buds will not appear. As a result, you will be deprived of flowering next year or this year.
The second case is when you prune a magnolia at the right time but too heavily. As a result, the tree will not be able to produce a sufficient number of flowering buds. It will also take a long time to recover from such pruning.
How to fix
Prune the magnolia as soon as it has finished flowering. This usually happens in spring. If you prune as soon as the flowers have faded, the tree will produce new branches with flower buds by mid-season.
Don’t cut back the magnolia too much. Only shorten the top part of the branch. If you cut too much, you will have to accept the fact that you will not see any flowers next year.
Pests and diseases
Both pests and diseases can greatly weaken a magnolia. This can lead to very poor blooms or no flowers at all.
If we are talking about pests, the most common ones are aphids, scale, and some other sucking insects. They all feed on the sap of the tree, and once they are too many the tree will stop blooming.
Regarding diseases, the most common fungus that affects magnolia trees is powdery mildew.
How to fix
Against insects, you need to use an aqueous solution of horticultural oil. Spray the magnolia twice at two-week intervals. If that doesn’t work, use a systemic insecticide.
Spraying with horticultural oil also works well against powdery mildew. However, if that doesn’t work, use a fungicide.