Why do marigold leaves turn yellow? (2023)

Why do marigold leaves turn yellow?

Aster Yellows – When you have marigolds with yellow leaves, your plants may be infected with a disease called aster yellows. Aster yellows is caused by a very small organism known as a phytoplasma. When this phytoplasma gets into the leaves of plants, they are discolored to yellow or red.

Colors include deep orange, golden yellow, lemon yellow, orange, red and gold bicolor, red, and yellow. Signet Marigolds (Tagetes tenuifolia): Small and bushy with fernlike, lemon-scented foliage, signet marigolds have leaves that are much lacier than those of other species.

The yellow-green color is likely due to a nutrient deficiency. Nitrogen and phosphorus deficiencies sometimes occur when flower and vegetable seedlings are started indoors. Symptoms of a nitrogen deficiency include yellow-green foliage and stunted plant growth.

Your marigold plant may wilt with too much water or too little. Keep in mind that a marigold plant that is wilting does not necessarily always need water. Sometimes marigold plants wilt when they have too much water. Always check the soil dryness to determine if you should give the marigold plant some water.

The most common nutrient problem associated with chlorosis is lack of iron, but yellowing may also be caused by manganese, zinc, or nitrogen deficiencies.

Marigolds don't require deadheading, but if dying blossoms are regularly removed, it will encourage the plant to continue blooming profusely. When you water marigolds, allow the soil to dry somewhat between waterings, then water well and repeat the process. Water more in high heat. Do not water marigolds from overhead.

Water the marigold when the top 1 to 2 inches (2.5 to 5 cm.) of soil is dry. Water deeply, then let the soil dry before watering again. Never allow the soil to remain soggy, as wet conditions invite root rot and other moisture-related diseases.

Sweet and golden like the flower it's named for, our April color of the month is marigold! This rich yellow is somewhere in between a bright yellow and darker mustard color, making it a lovely complement to both spring and fall decor. The color marigold gets its name from the flower of the same name.

Generally when a houseplant leaf turns yellow, that leaf is dying. Chlorophyll gives a leaf its green color. When the leaf loses its chlorophyll, the plant abandons it and begins to absorb leftover nutrients from the leaf. That's why once the leaf turns yellow, you generally can't make it turn back green again.

Should you cut yellow leaves?

Pulling Away Yellow or Brown Leaves

Trimming or plucking away yellowing or dead leaves is an easy way to help prevent any unwelcome plant pests from settling onto your plant, which are attracted to decaying or dead leaves more than healthy ones, and they are more likely to appear on a struggling plant.

To add potassium to an organic garden, cut up banana peels into small pieces and bury them 1 to 2 inches in the soil. Alternatively, mix in a few handfuls of dried kelp meal, or spray the soil with a liquid seaweed spray.

Signs of overwatered marigolds are wilted, yellowing foliage on the plant. Other signs include root rot and fungal growth on the plant which will compromise the health of the plant. Established marigolds should only be watered once weekly when the top inch of the soil is dry to touch.

Water marigolds once a week down to one-and-a-half inches. Always keep tagetes' soil gently moist by watering them to an inch deep twice per week from late spring to early autumn. If in a pot, check tagetes flowers daily and water if the top half-inch of soil is dry.

Marigolds need moisture to power blooms and soak in nutrients through their roots and foliage. For maximum blooming, marigolds growing in bed spaces should get at least an inch of water per week. Either by rain, or by watering. Proper watering is important to keep marigolds producing new blooms.

Overwatering

Watering issues are generally the most common cause of yellowing leaves. When your plants are overwatered, the performance and vigor decrease. Oxygen is being pushed out of the soil, and the roots are simply “under aired” and suffocating.

Magnesium deficiency

Symptoms: Yellowing between the leaf veins, sometimes with reddish brown tints and early leaf fall. Magnesium deficiency is common in tomatoes, apples, grape vines, raspberries, roses and rhododendrons.

The most common reason that plants' leaves turn yellow is because of moisture stress, which can be from either over watering or under watering. If you have a plant that has yellow leaves, check the soil in the pot to see if the soil is dry.

To review, plants suffering from nitrogen deficiency tend to be pale yellow-green in color and have slow or stunted growth. Yellowing from lack of nitrogen starts at the older leaves and moves on to newer leaves as the deficiency continues with yellowing patterns varying by crop.

How can I add nitrogen to my soil fast?

Marigolds can be overwatered, and this leads to root rot. Fungus may form on overwatered marigolds. Wilting and drooping are additional signs of excessive watering. Always allow the soil to dry out between waterings to avoid these problems.

A complete fertilizer with a nitrogen count of 100 to 150 parts per million with a balance of nitrogen and potassium, such as a 15-15-15, provides the best nutrient value for marigolds. Avoid ammonium fertilizers when the soil temperature falls below 65 F.

It is best to water marigolds at the base of the plant and not from overhead. The densely double flowerheads will tend to rot with excess moisture. Allow the soil to dry somewhat between waterings, but do water regularly in high heat or dry weather.

Too Much Rain or Humidity. African marigolds might stop blooming or the existing flowers will close up and rot if you have a ton of rain or extremely high humidity. They simply don't like that much moisture and they'll react negatively if they receive more than they prefer.