Mexican Sunflower: Diseases and Remedies (Explained for Everyone)

NOTE: In this article, Mexican Sunflower and Tithonia rotundifolia may be used interchangeably; in fact, Tithonia rotundifolia is the botanical name for Mexican Sunflower.

At the end of winter, gardeners rush to the garden center to find a fast-growing plant that will transform the landscape in a few months, like the Mexican sunflower.

Why does my Tithonia rotundifolia roots have rot?

Root rot on your Mexican Sunflower (Tithonia rotundifolia) can be dangerous if left untreated. In order to keep your plant alive, we strongly suggest that you follow our advice if the signs start to show: blackened and mushy roots.
Mexican

Why does my Mexican Sunflower have gray mold spots?

A particular fungus known as gray mold spots spreads quickly and frequently damages flowers. This fungus is probably to blame if you see any brown (or gray) spots. If you disregard these warning signs, your plant could die.

Our Solution

When you understand the root of the issue, the solution makes perfect sense. The majority of the time, it is caused by the Tithonia rotundifolia being overwatered. We urge you to cut off the infected roots and leaves, remove the affected sections of the plant, and then repot your plant in a fresh container with sterile potting soil.

Why does my Mexican Sunflower have leaf spots?

Leaf If your plants exhibit symptoms like rapid color changes in the leaves or leaves that wilt or droop, we give you all the information you need to recognize them and rescue your plants. For owners of Mexican Sunflower, this kind of illness is among the most distressing.

Why are my Mexican Sunflower leaves turning yellow?

In the world of horticulture, yellowing leaves are undoubtedly the most common problem. The two main causes of this problem are overwatering and a lack of nutrition.

When it’s overwatering, simply reduce your watering frequency, and if you think it’s a nutrient deficiency, here’s how to check it:

Here are some signs of yellowing caused by the many deficiencies on the Tithonia rotundifolia in question:

  • The first symptom of a magnesium deficiency is yellow patches between leaf veins on elder leaves. The leaf’s core turns yellow while the veins stay green. The edges of the leaf yellow last.
  • Yellowing between leaf veins is another sign of iron shortage, but young leaves on plant tops and branch tips are initially affected.
  • Sulfur shortage first affects the youngest leaves, turning them entirely yellow.
  • Potassium deficiency shows itself when leaf edges turn bright yellow, but the inner leaf stays green. Older leaves show symptoms first, and leaf edges soon turn brown.
  • A lack of nitrogen is indicated by a widespread yellowing. Older, inner leaves are the first to yellow. As the yellowing progresses, it eventually touches young leaves as well.

Our Solution

You only need to act in accordance with the symptoms listed above. You can address a potassium or nitrogen deficiency by buying a particular soil, and a gardening store consultant will be able to advise you on how to do that. Furthermore, you can also limit how frequently you water your plants.

Is my Mexican Sunflower sunburned?

It is quite easy to find out if your Mexican Sunflower (Tithonia rotundifolia) has been burned by the sun. Just like on us, your plant will change color in this case, it will start to turn yellow or white.

Sunburned

As we saw above, the leaves of your Mexican Sunflower can also change color if it receives too much water or insufficient light.

To find out if the yellow leaves have been sunburned, look at the part of the bottom that is tinted closer to the base. The yellow leaf is probably burnt and not something else if this portion stays greener.

Why are my Mexican Sunflower leaves turning brown?

The classic sign that a plant has been overexposed to direct sunlight and sunburned is the development of browning leaves. Rest assured that while this may probably save your plant from dying, it will adversely affect its growth.

Should I leave my Tithonia rotundifolia in direct sunlight?

No! Don’t leave your Tithonia rotundifolia (or Mexican Sunflower) in the sun if it displays the symptoms mentioned above; that’s why it’s in such a bad situation.

Our Solution

As explained in the paragraph above, the solution is simple, just place your Mexican Sunflower in a place where the light does not reach it directly, in this way and with a correct watering, your plant should resume its life rather quickly.

Why are my Tithonia rotundifolia leaves drooping or wilting ?

When you become dehydrated, this usually happens. Large plants are more vulnerable since they need more water on a regular basis than smaller plants.

Drooping

An easy way to know if your Tithonia rotundifolia is lacking water is to under-weigh its pot, if it looks light, it means that the soil and the roots are probably quite dry, and therefore need water!

Our Solution

If the soil in your plant’s pot is completely dry, you will need to start by moistening it so that the roots will also benefit from the water. A common mistake is to drown the Mexican Sunflower right after a dry period thinking that it needs a lot of water.

This is the case, but giving too much water at once is the best way to finish it off, you should actually water the soil normally, resuming a quiet watering rhythm.

Caring Tips for Tithonia rotundifolia

Water Occasionally

Your plant needs water to survive, but it’s crucial to balance the amount and timing of watering. As we previously mentioned, overwatering could be catastrophic for your Tithonia rotundifolia.

The best way to know if your plant needs water or not is to touch the soil, if you feel it is still wet, it is probably a good idea to wait a few more days.

Always keep temperatures stable

It’s also a good idea to keep your Tithonia rotundifolia at a constant temperature, especially if it’s kept indoors. In general, at GreenShack, we suggest booking a temperature between 65 and 85 degrees F. Of course, keep your Tithonia rotundifolia away from radiators, air conditioners, and other sources of hot or cold air.

Keep your Mexican Sunflower Dust-Free

This one is about houseplants. Your indoor plants’ leaves get dusty just like your furniture does. The problem is that this might prevent photosynthesis from beginning, which would result in the plants gradually losing their color.

This would be a true journey into hell for your Mexican Sunflower and would also satisfy the pests.

To remove the dust from the leaves of your plant, take a microfiber cloth and gently rub the leaves. You can wet the cloth to make it easier to remove the dust, but never use corrosive products (such as rubbing alcohol!)

Keep drainage in mind

If you have a tendency to overwater, you need to keep an eye on your drainage, we advise you to opt for a pot with drainage holes if it is not already the case and a saucer.

In the meantime, if you don’t have holes in your pots, you can add volcanic rocks (or any rocks with holes) at the bottom of your pot, this way it will create a channel so that the water doesn’t stay in your skin too much (to avoid that roots start to rot!)