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Why Are My Dahlias Wilting? (5 Common Causes)

Why Are My Dahlias Wilting? (5 Common Causes)

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Dahlias are very popular in many garden settings. These plants are so vibrant, and they will definitely add a touch of color to your yard.

The flowers of the dahlias are especially appealing. Depending on what you bought, the flowers can be pale yellow or they might turn out to be bright pink.

You want to be able to enjoy your dahlias to the fullest. This is why it’s so frustrating when you notice that the dahlias are wilting.

What causes these plants to start wilting? If the plants are wilting, then does this mean that you did something wrong?

Read on to learn what you can do about wilting dahlias. This will show you why these plants might wilt so that you can do your best to keep them healthy and avoid making common mistakes.

1 – Watering Issues

Dahlias may wilt due to watering issues

The most likely reason why your dahlias are wilting has to do with watering issues. If you don’t water the dahlias enough, then they’re eventually going to start wilting.

All plants need to be watered every so often. Some new plant owners will forget to water their plants and wind up having them die.

This is very common for houseplants, but it can happen with outdoor plants as well. The dahlias might not be able to survive in your yard just on the water that they receive from natural rainfall.

If there hasn’t been much rain lately, then there’s a good chance that you’re going to need to go outside and water the plants. Of course, you only need to water the plants so much.

Going overboard with watering can lead to problems as well. If you water the plants far more than you should, then the dahlias could wilt due to drowning in water.

When caring for dahlias, you’re supposed to ensure that the soil stays moist. It should be moist about twelve inches into the soil.

You need to keep the plant from having problems with root rot. For this reason, it’s necessary to plant the dahlias in soil that drains really well.

So the issue could be that you’re not watering well enough or it could be that you don’t have the dahlias in good soil. If the soil doesn’t drain right, then everything will get soggy and the health of the plant will be in jeopardy.

Use well draining soil for the dahlias and consider adding a mulch layer to retain moisture. This can also be good for keeping weeds from bothering the dahlias.

2 – Excessive Sun

Excessive sun can be to blame for your dahlias drooping. The plant drooping is a bit different from it wilting, though.

When it’s really hot outside, the dahlias might start to droop a little. This happens because the plant is trying to protect itself from stress by diverting water to its roots.

This occurs at the expense of the leaves and stems. So the plant will wind up looking a little droopy when the sun is really hot.

As the sun goes down or things get a bit shadier, the dahlias should perk back up. If the soil is moist, then the dahlias should be just fine.

This is why many people refer to this situation as “daytime droop.” If you don’t want this to happen to the dahlias, then you can protect them from the harshness of the sun with a little bit of shade.

If you’re caring for dahlias in containers, then you can just move them to a shadier spot during the hottest parts of the day. If they’re in the ground, then you can come up with other methods to provide the plants with partial shade.

3 – Crowded Roots

Crowded roots can be a big problem when you’re growing dahlias in containers. It could be that the roots are too crowded in the container, and this might cause the plant to start wilting.

To get good results, it’s recommended to keep just two small tubers in one eight-inch pot. It’ll also be necessary to choose a good pot.

Some have had very bad luck when using terracotta pots for dahlias. They don’t retain moisture as well as some other pots due to being overly porous.

You can still raise dahlias in those pots fine if you keep an eye on them, though. It’ll simply be necessary to check soil moisture daily to ensure that everything is as it should be.

If the dahlias outgrow the pot, then you’ll need to give them a bigger pot. Avoid putting dahlias in pots that are too small or trying to cram too many tubers in one pot.

4 – Pest Issues

Dahlias may wilt due to pest issue

It wouldn’t be unusual at all for dahlias to wilt due to having pest issues. There are many pests such as aphids that have been known to bother dahlia plants.

Pests such as mites and aphids will actually suck the juices right out of the stems. This makes it tougher for the dahlias to thrive, and they might start wilting due to the damage that the pests are doing.

There are even some pests that make it so that the plant isn’t able to use its roots to take water normally. If a plant can’t utilize water as normal, then it’s definitely going to wilt.

Pest issues could wind up killing your plant if you aren’t careful. Severe pest infestations should not be ignored.

Some infestations such as nematode infestations can be so severe that you won’t be able to save the plant. When such an infestation occurs, it’s recommended to discard the plant and immediately treat the soil in an attempt to keep the pests from spreading to other plants in the area.

Aphids and mites will be easier to deal with. Depending on what type of pest you’re dealing with, you might need to use pesticide.

Some also treat their plants with neem oil to ward off pests. Try to keep an eye on your dahlias so that you can catch issues with pests early.

5 – Diseases Can Cause Wilting

As you might expect, diseases can cause wilting. Your dahlias could have some type of problem that is making them wilt.

Watering the plants too much or keeping them in soil that doesn’t drain well will be problematic. This can lead to issues such as root rot.

Big problems such as verticillium wilt have also been known to impact dahlias. The best thing to do is to prevent these diseases from happening in the first place.

Use well-draining soil and only water your dahlias as much as is necessary. Also, never grow dahlias in the same soil where diseased dahlias used to be.

Final Thoughts

Learning about why dahlias wilt should help you to turn things around. You know that dahlias most commonly wilt when you don’t water them enough.

It might be a simple case of you needing to keep the soil moist so that the dahlias can thrive. Then again, you might be watering the plant way too much and causing it to experience root rot.

Remember to keep your dahlias in well-draining soil. This is going to be important whether the dahlias are in the ground or if you’re growing them in containers.

Watch out for the dahlias in containers since they can become rootbound. Don’t try to force too many tubers into a tiny pot.

If you’re able to watch out for pest issues and problems with diseases, then you should be able to protect your dahlias well. They’ll look pretty in your garden for a long time to come.