The zinnia is one of the most beautiful flowering plants in the world. It has some of the most beautifully colored flowers that you will ever see, and it’s a fantastic plant for people who want to paint their garden in multiple hues.
The zinnias are generally quite hardy plants, but they can be exposed to different situations that can cause the plant to turn brown and eventually die.
The zinnia generally has lush green foliage, so if you notice the leaves turning brown, it’s a pretty clear sign that there’s something wrong with your plant. However, figuring out the problem is definitely not as easy.
There are a number of different problems that may affect the zinnia, ranging from diseases to problems with the way you grow the plant. In the following paragraphs, we will identify a few problems that could affect your zinnias, and what you can do about them.
Alternaria Leaf Spot
One of the most common diseases that can cause the leaves of your zinnia to turn brown is Alternaria leaf spot. This is a fungal disease that doesn’t just affect zinnias, but several other plants.
It can also have a devastating impact on tomatoes, lettuce plants, and even sunflowers. The disease manifests itself through the appearance of reddish-brown patches that begin to appear on the leaves.
With time, these patches will develop tan or gray-white centers. As time passes, these spots will continue to grow in size, until the whole leaf is covered.
With the passage of time, the center will disappear from the spots, and the entire plant will start to look ragged. Holes will appear and the leaves will begin to fall off.
If you do not treat this problem quickly, the foliage will wilt, and it will turn completely dry and brittle. You have to take action right away. There are fungicides available in the market that are able to combat this problem.
Make sure you get in touch with an arborist so that they can recommend a suitable fungicide for treating your zinnias.
Bacterial Leaf Spot
Another major problem is the bacterial leaf blight. Unlike the previous one, which is caused by a fungal infection, this one is caused by bacteria. It starts off subtly, and you will notice translucent spots appearing on the flowers or the leaves.
With the passage of time, yellow halos will appear, and they will eventually turn brown. As the spots continue to grow larger, the centers turn browner and browner until the whole leaf is covered.
Over time, the plant will wilt and decay if you do not treat it. This is a serious problem, and in most cases, your only option will be to get rid of the affected parts of the plant and then let the plant grow again.
If you are not careful, your zinnia will succumb to a premature death.
Caring for the Zinnia
These are two of the most popular diseases that can affect the zinnia. However, diseases aren’t the only reason why your plants might begin to turn brown.
One of the key components of zinnia care is watering the plant. The zinnias expend a great deal of their energy in flowering, so the plant needs an adequate amount of water and nutrients to replenish its stores.
When watering the plant, make sure that you do not water the leaves. If you are going to leave the plant out under the open sky, it could cause the plant to suffer from sunburn.
You don’t want that, so the best way to deal with this problem is to make sure that you water the plant only at its base. You might want to consider making use of a soaker hose.
They are suitable for keeping the foliage and the flowers completely dry while you continue to provide water to your plant. If you have a full garden of zinnias, opting for a drip irrigation system is another great idea.
More importantly, the time at which you water your zinnias is also equally important. Ideally, it is best if you water your zinnias in the early morning.
This gives the leaves and the flowers a great deal of time to dry out properly before the sun goes down. Watering your zinnias, or any other plant, in the night is a terrible idea.
When you water the plants in the night, the water is unable to evaporate properly, and as a result of that, the plant may actually suffer more. On the other hand, when you water your zinnias in the morning, the water will evaporate by midday.
Remember, the soil of your zinnias should ideally remain moist, but make sure it’s not soggy. This is even more important for the younger plants.
The mature zinnias do not need as much water as the young ones, mainly because the full-sized ones are able to tolerate drought much better than the younger ones.
With the right placement in your garden and the provision of the right quantity of water, your zinnia is going to add color in your garden for years to come. If you want, this plant can also be added with others in your vegetable garden as well.
See my article on what companion plants to grow with zinnias.
Another important thing that’s necessary for the zinnias is deadheading. Remember, this plant gives off a host of flowers and then needs time to recover.
Deadheading is the simple way of promoting more blooms by cutting off dead or dying flowers. When you notice that a flower has completed its life cycle and has begun to wilt, you should consider using a pair of scissors to remove it.
Make sure you only remove the flower stalk because that’s going to allow the plant to save on more energy. It’s a fairly simple way of making sure that your plant remains healthy all year round.
While the zinnia is an incredibly hardy plant, you should know that it is prone to a few bugs. For instance, a common problem that might impact your zinnias is powdery mildew.
This is a disease in which your plants turn a shade of white and then eventually go brown. Taking swift action is necessary if you want to treat the powdery mildew problem.
Pest infestations caused by aphids or mites are also serious issues. They aren’t going to chew all the way through the plants and create holes, but you will notice that your leaves will begin to curl or mottle.
It’s also entirely possible that your zinnias are exposed to more than one problem. In that situation, it is important for you to get in touch with an experienced gardener.
Unless you know a thing or two about gardening and the many problems that can affect your zinnias, it is a wise move to avoid experimenting. You should contact a local gardener to visit your place and then inspect your zinnias.
They will let you know about the problem and then give you a better idea about how to treat it. These are just some of the many reasons why your zinnias might begin to turn brown.
As long as you take care of the problem, it shouldn’t take too long before they get back to normal.
Growing up with a mom who filled her home (inside and out) with all sorts of plants, Lisa got her start in gardening at a young age. Living now on her own with a home and yard full of plants (including an indoor greenhouse), she shares all the gardening tips she’s gained over the years.