2 images: a closeup of an overwatered houseplant with yellowing leaves, and a closeup of an underwatered houseplant with yellow, crispy leaves

3 Reasons Plants Turn Yellow and How to Help Them

We all know that leaves can turn yellow, orange and red during the fall. But the yellowing of leaves at other times of the year can be a perplexing part of being a gardener. Do you feel like you’re doing everything right and they’re still turning yellow? Below are key things to take into consideration that can contribution to yellowing leaves.

Houseplant in a round white pot on a wood surface with a yellowing leaf

3 Reasons Leaves Turn Yellow

1. Watering

Water is a tricky problem when it comes to gardening and plant health. If you’re experiencing a yellowing of leaves or branches, think about how much you are watering—both in terms of the quantity of water and the frequency. Yellowing can be a result of too much or too little water:

  • Do you plants have yellow, mushy centers? Is so, you are likely over-watering your plant. 
    • Try cutting down the frequency with which you water and allow the soil around your plant to slightly dry out in between waterings. 
    • The right soil can make all the difference. Not sure which soil you should use? Speak with one of our Trusted Garden Advisors to learn more. We have the right soil for your every planting need. 
    • Another thing you’ll want to ensure is that your plant isn’t sitting in water runoff that’s being captured by the tray under your pot. It may take a few minutes for the runoff to appear. We recommend watering your plants and then revisiting them to make sure there’s no excess water in the tray. If there is, empty it. 
  • If your plant leaves are dry, crunchy and yellowing, then the problem may be due to under watering. We recommend trying the following: 
    • Give your plant some water a little more frequently and see how it responds. 
    • Ensure that the root ball of the water is getting a throughout, deep watering (avoid shallow watering). 
    •  To learn more about watering in containers, read our blog “Common Misconceptions About Watering Plants In Containers.”

2. Nutrition

Watch out for strange yellow patterns on leaves; this could be a strong sign of nutritional issues. For example, if the veins on the leaves are green and the tissue is yellow, that is almost always a sign of poor nutrition. Follow the guide on your fertilizer to make sure your plants aren’t receiving too much or too little. For fertilizer recommendations, speak with one of SummerWinds Nursery’s Trusted Garden Advisors. We have a wide variety of fertilizers for all of your indoor and outdoor gardening needs.

3. Sunburn

Closeup of a plant leaf that was burned by the sun

Another reason your plants may be turning yellow is that even plants can get a sunburn, just like you! In Arizona, the afternoon sun can be particularly harsh. If possible, create shade or cover the leaves for a few hours during the day. However, don’t restrict all sunlight from your plants. A strategically placed shade cloth can make a big difference in your plant’s health. We recommend positioning the shade cloth around the plant to help the plant avoid mid-day or late afternoon sun.

If your plant is sunburned, it’s best not to cut back or trim any sun burned leaves at this time. The damaged leaves will protect the foliage beneath if there’s another hot day with damaging sun. Lightly trim them back when temperatures cool, but don’t do any heavy pruning until early spring.

Light also plays a part in the yellowing of leaves. As Ambius states, “This occurs because the rate of photosynthesis is limited in low light, but as the light is increased, photosynthesis increases as well.” To make sure your plant is getting the right amount of sun, read the recommendations on the labels. However, keep in mind that plant labels are general use and not designed for specific regions. It’s important to keep in mind how strong the sun can be in the Valley of the Sun and account for that in the exposure your plant receives. If you have questions, speak with one of our Trusted Garden Advisors for recommendations based on our local climate.

An assortment of different types of potted houseplants lined ina row on a table

Keeping Leaves Healthy

The health of your plant’s leaves is important and there are small, but mighty adjustments that can be made. Watch water levels, nutrition and sunlight to protect them from turning yellow. Stop by your local SummerWinds Nursery to learn more.