If your sweet pea shrub turning yellow there is no need to worry, as it is mainly because of watering issues, nutrient problems, pests, and diseases.Sweet Pea Shrub Turning Yellow

In this article, we will tackle each one, discuss what we can do to solve it, and apply precautionary measures, too. Keep reading to learn more!

Why Is Sweet Pea Shrub Turning Yellow? 9 Common Reasons

Nine common reasons why your sweet pea shrub is turning yellow include watering issues and root damage. Over-fertilizing, insufficient light, temperature issues – too high or too low, manganese and nitrogen deficiency are also problems. Finally, there may be a pest infestation or disease.

– Watering Issues

The yellowing of the leaves is one of the most common signs of overwatering peas, along with stunted development and root rot. As a result, nitrogen will be pushed out of the soil and away from the roots. It can also compact the soil, which will prevent the roots from receiving the nutrients they require and cause them to rot.

Not providing enough moisture is also not good, as it will lead to stunted growth and the yellowing of leaves. Your pea plants’ leaves could also turn yellow if they are under water.

– Root Damage

The yellowing of leaves can also be an indication that the roots are damaged or compacted. Given that your plant is root-bound, the roots are inefficient and cannot deliver the required nutrients to the plant. Another cause is root rot, which is caused by a different fungus that lives in the soil and harms sweet peas. The bottom stalks of growing plants eventually turn yellow-colored, indicating that they are dying.Reasons of Sweet Pea Shrub Turning Yellow

– Over Fertilizing

For sweet peas to thrive well, nutritional levels must be balanced. For instance, phosphorus components promote the flowering of sweet pea flowers, whereas nitrogen aids in the production of chlorophyll. So, adding these nutrients through fertilizer is a common practice.

However, a high nutrient dosage can cause leaf yellowing, stunted growth, leaf drop, and brown leaf tips. You will know that you are overfertilizing if there is a salt coating covering the soil’s surface.

– Insufficient Light

Pea plants in deep shade may start to develop lighter or yellower-colored leaves. Peas need at least six hours of sunlight per day to grow quickly. An adequate amount of sunlight will also help the peas, flowers, and the production of green chlorophyll in their leaves.

– Temperature Issues

A sudden temperature change is generally not tolerated by plants. For sweet peas, it cannot handle temperatures above 65 degrees Fahrenheit, as their leaves may turn colored yellow to brown.

– Manganese Deficiency

The yellowing of the leaves of the sweet pea plant can also be a symptom that the plant is lacking manganese. Manganese is essential for photosynthesis, and a shortfall will result in chlorosis, which is often noticed in soil with a very high pH.

– Nitrogen Deficiency

Another nutrient inadequacy that results in the yellowing of the leaves of the sweet pea plant is nitrogen deficiency. Even though peas are legumes and can fix nitrogen from the air in very poor soils, they still occasionally suffer and turn colored yellow.

– Pest Infestation

The intensity of the infestation will determine whether the leaves are yellowed, mottled, or have round or white-gray spots on them. The mild fall weather makes it possible for insects to appear fast and damage the plants.Pest Infestation in Sweet Pea Shrub

Sweet pea plants can be harmed by common pests, such as scales, aphids, slugs, snails, leaf miners, caterpillars, pea weevils, and even birds. These pests suck the sap from the leaf. Scale or aphids, which sit on the veins of leaves, sucks away the nutrients and water, which causes damage to the plant. This will then result in the leaves turning yellow and then brown.

– Diseases

Pea mosaic virus is one of the common diseases that sweet pea plants contract. Once affected, the sweet pea’s leaves may become mottled and yellow. Leaves with dark green and yellow-green patches are a sign of the condition, as well as vein clearing and stunted growth.

There is also the grayish-white growth known as powdery mildew, which can be seen on the stems and leaves of affected sweet pea plants. Infected leaves will turn yellow and wither as the fungus spreads.

Another one is the spotted wilt virus. It generates circular, first yellow and then brown dots on leaves, which are often propagated by thrips.

Fusarium wilt is another infection that causes the plant’s body to wither away and its foliage to become yellow. However, the stalks’ foundation is not affected. The fungus keeps thriving in the soil and penetrates the pea plant’s root system.

What Can You Do to Prevent Yellow Leaves on Sweet Pea Plants?

To prevent yellow leaves on sweet pea plants you can ensure you water properly, use mulch and place them somewhere with direct sunlight. You should also avoid too high temperatures. Maintain balanced fertilizers, get rid of infected plants and use fungicides.

– Water Properly

Although sweet pea plants only require weekly watering, it’s important to maintain balanced moisture levels all through the growing season. However, before you start watering them, check the soil for one to two inches below to see if it is dry.

To avoid overwatering, just water when the topsoil has begun to dry up. Rainwater is ideal for peas because it has trace levels of atmospheric nitrogen that will aid in the development of their green leaves.

– Use Mulch

You can also mulch the plant with straw or bark mulch to help control how much water penetrates through the soil. The additional water in bark mulch will be absorbed and released gradually over time. Reduce the frequency of your waterings, and give the soil a chance to somewhat dry out between applications.Solutions to Sweet Pea Shrub Turning Yellow

– Place in a Location with Direct Sunlight

To flourish, sweet pea plants require direct sunshine. Move the plant container to a more advantageous spot where it will receive enough sunshine. Pick a spot that receives sufficient morning sunlight and afternoon partial shade.

– Avoid Temperatures Above 65 Degrees

Choose a location that protects the plant from high temperatures. You can use a curtain to avoid sweltering sunlight or shift the pot indoors.

– Maintain Balanced Fertilizers

Your plants should primarily be treated with a general-purpose fertilizer in the spring and fall because they sprout throughout the year. So, every two weeks, feed the sweet pea seedlings nothing more than an all-purpose fertilizer.

To boost the nitrogen levels in peas planted in a garden bed, scatter a few handfuls of pelleted chicken manure over the plant’s root zone. New leaves will begin to turn green during this period, and the vine’s ends will begin to grow tall and green.

– Get Rid of Affected Plants

With short-lived annuals like sweet peas, there isn’t much you can do about it once they are severely affected by a disease, and it isn’t worth the effort to try and save the plant. If the plant is looking bad, you might want to remove the sweet peas to lessen the chance that the disease will spread.

– Use Pesticides

Use fungicides available in the market to get rid of common pests. Scale can be effectively treated using Eco or Neem oil. If there are only a few bugs, use a strong water jet to spray them away, but make sure to inspect your plant every day because pests can quickly multiply and take over.Details of Yellow Sweet Pea Shrub


Once you determine what is causing the issue, you can quickly attend to it. Let us recap what we have learned:

  • The most common cause of sweet pea plants to become yellow is poor watering. If you miss a day, it might dry out too much or get excess water. In both cases, it will result in leaves’ yellow color.
  • Trim off the yellow leaves on pea plants. Once provided with the nutrients and water they require, peas are resilient and will bounce back.
  • Yellow leaves are typically caused by an insufficiency of manganese or nitrogen. You can check the pH of your garden soil and add sulfur if necessary to adjust it.
  • Pea mosaic virus, spotted wilt, and fusarium wilt are diseases that can result in the yellowing of sweet pea plants.
  • Planting in well-draining soil, rotating crops, and removing and destroying sick plants can all help prevent yellow leaves on sweet pea plants.

Now that you have all this information on hand, the yellowing leaves of your sweet pea plants will just be a thing of the past!

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