Closed Magnolia Buds: Reasons For Magnolia Blooms Not Opening

(Image credit: yanjf)

Most gardeners with magnolias can hardly wait for the glorious flowers to fill the tree’s canopy in springtime. When the buds on a magnolia don’t open, it’s very disappointing. What is going on when magnolia buds won’t open? Read on for information about the most likely causes of the issue, plus tips on how to make a magnolia bloom.

About Closed Magnolia Buds

When you see abundant magnolia buds on your tree’s branches, you’ll be hoping for a canopy full of flowers in spring. When those magnolia buds won’t open, the first things to look at are cultural practices, including the amount of sun and irrigation the tree is receiving in its current location. Magnolia trees need lots of direct sun in order to produce flowers. The more shade your tree gets, the fewer flowers you will see. Even if you planted it on a clear, sunny site, nearby trees may have grown tall and currently be shading it. If those closed magnolia buds are not getting much sun, you’ve figured out the problem. Likewise, magnolia trees don’t do well with too much nitrogen fertilizer. If you notice magnolia blooms not opening, check to make sure your trees get enough, but not too much, feeding. Magnolia buds set in the fall to open in the spring. During their wait, a lot of weather happens that can result in your magnolia blooms not opening. If winter weather is wet, the closed magnolia buds can rot. Cold fall weather can bring frosts earlier than usual before the buds are prepared for it. This can prevent flowers in spring. If the closed buds are falling from the tree in spring instead of opening, this may well be a sign of damaging spring frosts. Another possible cause of this problem is an attack by an insect called a thrip. If thrips attack magnolia buds, they won’t open. Check buds for brown trails on petals and apply an appropriate pesticide.

How to Make a Magnolia Bloom

If you are wondering how to make a magnolia bloom, there is no one secret to success. However, selecting a cultivar appropriate for your hardiness zone is essential. If buds on a magnolia don’t open for several years in a row due to weather, you might want to transplant your tree to a more weather-protected area. You can also try using protective covering during frosts of autumn and spring. If you discover that your tree is in shade, you know why you see magnolia blooms not opening. You need to trim back neighboring trees or move the magnolia to a sunnier location.

Teo Spengler

Teo Spengler has been gardening for 30 years. She is a docent at the San Francisco Botanical Garden. Her passion is trees, 250 of which she has planted on her land in France.