Tomatillo leaves turn yellow mainly due to Overwatering. They may also turn yellow due to Nitrogen deficiency. Magnesium deficiency causes yellow spots on the leaves. In rare cases, they get infected by Psyllid yellows. Yellow spots appear on the leaves of Tomatillo in one of the stages of Downy Mildew disease.
Tomatillos are closely related to tomatoes. They do not taste like tomatoes but like lemons and herbs.
Tomatillos are native to Mexico. Tomatillos are sometimes also called husk tomatoes as they have a dry, leafy husk that wraps the fruit.
People often complain to me that their Tomatillo plants’ leaves are turning yellow. Let’s see why it happens and how to fix it!
Tomatillo leaves may turn yellow due to many reasons. In all honesty, it happens due to poor conditions that affect the plant.
Overwatering
Overwatering is one of the common reasons why Tomatillo leaves turn yellow. Overwatered plants fail to absorb required nutrients like Nitrogen, so they turn yellow.
If the older leaves are yellow and the newer leaves are just fine, it’s due to overwatering. Tomatillos need an inch of water per week.
Cut back on the water and it should recover just fine. Only water once a week, use drip irrigation if possible to measure the amount of water you supply.
Nitrogen Deficiency
Tomatillo leaves could also turn yellow due to Nitrogen deficiency. You may want to increase the Nitrogen content in the soil if you think it’s the cause.
Overwatering can accentuate Nitrogen Deficiency or make room for it. So, recall what you did recently that could have affected the plant and act accordingly.
If it’s indeed Nitrogen deficiency, add some fertilizer to the soil. Wait for a week and see the results.
Psyllid Yellows
Psyllids are insects that feed on plant juices. These insects are tiny and each species of this insect feeds on one particular plant/few closely related plants.
The yellowing of the foliage seems to be moving upward. Apart from the yellowing of the leaves, the veins may become purple.
Psyllid infection causes abnormalities in the growth of Tomatillos. Older leaves thicken and the bases roll upwards.
Excess or Lack of sunlight
Tomatillo leaves turn light green to yellow when the plant doesn’t get abundant sunlight. Move your potted plant to a brighter place for better growth.
Place your Tomatillo plant so that it neither gets too much sunlight nor in complete shade.
Nutrient Deficiency
Tomatillo leaves turn yellow when deprived of essential nutrients like Nitrogen, Potassium, or Sulfur.
Nitrogen Deficiency in Tomatillo
Old leaves of the Tomatillo plant turn yellow and fall off. All the leaves of the Tomatillo plant turn pale. The main stems and petioles become stiff.
You can add organic manure to increase Nitrogen content in the soil. You can use quick-release Nitrogen fertilizer for faster results.
Potassium Deficiency in Tomatillo
Tomatillo fruit remains green near the stalk when it’s deprived of Potassium. Leaf edges turn yellow and dry up when the plant doesn’t get sufficient Potassium.
Sulfur Deficiency in Tomatillo
Sulfur deficiency symptoms are similar to that of Nitrogen deficiency. The yellowing of the leaves starts at the top of the plant.
Eventually, all of the Tomatillo plant leaves turn pale green/yellow. Use appropriate fertilizer to fix this deficiency.
Diseases in Tomatillo
A variety of fungal infections can be found in Tomatillo plants. These fungal diseases usually start in the soil, so it is crucial to be wary of the initial symptoms of fungal diseases.
Tomatillo leaves turn yellow when the plant suffers from Early blight, fruit and stem rot, late blight, and Powdery Mildew.
Powdery Mildew doesn’t affect the quality of the Tomatillo fruit. All the other diseases make the Tomatillo fruits inedible. Pick the infected parts and destroy them immediately.
Destroy the entire plant if it is affected by stem rot and fruit rot to prevent the disease from spreading to healthy plants.
Yellow spots on Tomatillo leaves
Yellow spots are seen on Tomatillo leaves due to Downy Mildew, a fungal disease. Magnesium deficiency also causes yellow spots on Tomatillo leaves.
Yellow bumps on Tomatillo leaves
Downy Mildew can cause yellow bumps on leaves. It doesn’t start with a residue on the bottom of the leaves, symptoms are first seen on the upper side of the leaves.
Yellow spots on the leaves are not the usual symptoms of Downy Mildew. They are seen at a stage in Downy Mildew infection.
Magnesium Deficiency in Tomatillo
Do you see yellow spots on Tomatillo leaves? It’s probably due to Magnesium deficiency. Magnesium-deficient plants show yellowing and then become necrotic.
The leaves turn yellow between the veins. Magnesium deficiency can be fixed by adding Epsom salts to the affected soil in autumn or winter.
You can expect healthier foliage in the next season after adding Epsom salts to the soil.
Why are my Tomatillos Yellow?
Tomatillo fruits turn yellow when they are fully ripe. The tomatillo fruits turn yellow in color and drop off the parent tree.
Tomatillo fruits turn yellow once they’re mature enough to break the husk. It is safe to consume tomatillo fruits that turn yellow.