Ginger, of the family Zingiberaceae, is widely used as a spice and herbal medicine. These plants originated in Southeast Asia and were transported from there by Austronesian people. They thrive in tropical climates and tend to spread aggressively, which makes them popular garden perennials. Unfortunately, they are also prone to conditions and diseases that can cause yellowing leaves.
Ginger Leaves Turning Yellow: What Are The Reasons?
It could be due to bacterial or green wilt
Ginger leaves turning yellow could be due to bacterial wilt. This is a disease caused by bacteria and the initial symptoms are a slight wilting, curling and yellowing of the lower leaves. The discoloration will then progress upward, affecting the younger leaves. This is followed by a complete yellowing and browning of the entire shoot.
The foliage eventually dries up and becomes yellow-brown in three to four days. The succulent shoots become rotten and break off from the underground rhizome at the soil line. The underground parts become damaged and infected, and the rhizomes become discolored while their central parts have a water-soaked appearance. In advanced infections, they become entirely soft and rotten.
To fix the problem, make sure your garden has proper drainage to avoid stagnant water. You can also plant the ginger plants on miniature hills or mounds to elevate them.
It could be due to fusarium wilt or fusarium yellow
Ginger leaves turning yellow could also be due to fusarium wilt or fusarium yellow, which is caused by the fungus Fusarium oxysporum. The leaves of an infected ginger plant turn yellow and fall off, and the plant eventually wilts and dies. A unique symptom of this disease is the reddish-brown discoloration of the water-conducting tissue of the stems and roots.
There is no effective treatment for fusarium wilt; instead, you have to remove and dispose of affected plants immediately. Do not compost the garden refuse, but remove and replace fusarium-infected garden soil.
It could be due to dry rot
Your ginger plants could be infected with dry rot if you notice that the tips of the lower leaves are turning yellow. The upper leaves also begin to turn yellow as the disease progresses. The plant eventually becomes stunted and dried out, while the rhizomes develop a brownish ring.
Dry rot is caused by certain species of fungus and may also be caused by exposure to too much water. There is no cure for this disease, but you can increase the chance of avoiding it by planting treated seeds.
It could be due to rhizome rot
Rhizome rot is also called soft rot or Pythium rot, a soil-borne fungal disease caused by Phytophthora sojae. This disease causes stunted growth, rotted and mushy roots, yellow stems and roots, as well as foul-smelling rhizomes. It usually happens in environments where the soil is warm and wet.
To fix this problem, plant ginger plants on hills and use treated seeds and fungicides. If the plants have become infected, remove and destroy them at once so the disease does not spread to other plants. Keep your garden free of weeds and rotate the crops that you plant each year.
It could be due to white grubs
Ginger leaves turning yellow could also be due to white grub infestation. These are pests that feed on ginger rhizomes and leave behind big holes. The leaves will eventually turn yellow and may die. Adult white grubs are dark brown, while young larvae are white and live in the soil.
Eradicate white grubs by using neem oil or a vegetable fungicide. You can also plant crops like onion, sunflower or maize to deter white grub infestation.
Why are my ginger plant leaves turning brown?
Your ginger plant leaves could turn brown because of a lack of water. These plants prefer moist and well-drained soil with high humidity. If you fail to maintain a constant level of moisture in the soil, the leaves of ginger plants could turn brown.
Why are my ginger plant leaves turning white?
Your ginger plant leaves may be turning white because of a disease called leaf spot. This condition could lead to severe blighting and rotting of the leaves. The symptoms include small spots on the younger leaves along with a white center, a dark brown border and a yellow halo. The spots could turn into lesions that may cover the whole leaf.
The leaf spot disease spreads quickly and can be transmitted through rain and wind. To treat the disease, use herbicides containing boron, zineb or benomyl.
Ginger plants are widely cultivated because they are used as spices and also have health benefits and medicinal properties. Yellowing ginger leaves may be attributed to diseases like bacterial wilt, fusarium wilt, dry rot, or rhizome rot.
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