Verbena dies mainly due to overwatering, the leaves wilt and turn yellow. The plant dies due to waterlogged conditions. Verbena could also die due to underwatering, and fertilizer burn. Verbena is also prone to a fungal disease called Powdery Mildew.
You can prevent a variety of diseases in Verbena through cultural practices. Watering frequency is the main reason behind all the problems.
In this article, you’ll learn how to water Verbena properly. You’ll also know how to gauge the draining capacity of your garden soil.
Why is my Verbena wilting?
Verbena leaves wilt when the plant gets too much or too little water. People always seem to think that such plants need water, but it’s not always the case. It could also happen due to overwatering.
You need to check the moisture in the soil before watering your Verbena. Insert a finger into the soil around the Verbena plant.
Water your Verbena only if the top-half inch of the soil is dry. This is a good rule of thumb for the uninitiated.
Verbena leaves also wilt if the plant is given too much fertilizer. Verbena foliage also wilts if fertilizer is applied on a hot day. Use fertilizer according to the instructions to avoid such problems.
Why is my Verbena turning yellow?
Verbena leaves turn yellow when the plant gets too much or too little water. Verbena foliage also turns yellow due to fertilizer burn. Verbena leaves could also turn yellow due to iron deficiency.
You need to observe the signs your plant is giving you over a few weeks to diagnose the issue properly. Only act once you’re sure of the cause.
Can you overwater Verbena?
Yes, yellow foliage in Verbena can be caused by overwatering. People water a plant as soon as they see it drooping. Usually, indoor plants suffer from overwatering.
The fact is, you shouldn’t water such plants. Check why the plant is drooping. Check the soil around your Verbena. Is there a puddle around the plant?
Insert your finger into the ground and water only if the top half-inch of the soil is bone-dry. If the soil is water-absorbing, add some sand to it.
Stop watering your Verbena as soon as you know it’s overwatered. Your plant should recover after a couple of weeks.
Tip: Cut the top and bottom of a 46 oz. can. Dig a 4-inch deep hole near the plant. Place the can in this hole and fill it with water. If at least 2-inches of the water hasn’t drained in an hour, it’s time to move the plant to a place with better drainage.
Underwatered Verbena
Verbena turns yellow and wilts if it doesn’t get adequate water. Mulch in autumn to maintain adequate moisture levels in the soil.
Whenever in doubt, stick your finger into the soil, if the top half-inch of the soil is dry, give the plant some water.
You need to take special care of Verbena in the summer. Make sure your plant gets enough water to cater to its needs in the summer.
How often do you water verbena?
If Verbena is planted outside you need to water it 2/3 times per week. This is because outdoor plants get in contact with direct sunlight.
If the Verbena is planted indoors, it doesn’t need to be watered as often. Water only when the top half-inch of the soil goes dry.
In the fall season, you don’t need to water your Verbena frequently. Even the ones that are planted outdoors need water once a week.
Fertilizer burn
Verbena leaves can also turn yellow due to fertilizer burn. Too much fertilizer causes fertilizer burn in plants. Fertilizer burn also happens when fertilizer is applied on a hot day.
Verbena’s roots are burned due to fertilizer burn. You can prevent this by using fertilizer according to the instructions on the label.
Why is my Verbena turning brown?
Verbena leaves turn brown and a powdery white layer is formed on the leaves when the plant is suffering from ‘Powdery Mildew’ disease.
The disease can be avoided by enhancing the ventilation around your Verbena plants. Cut off the symptomatic leaves as soon as you see them.
Put these leaves into a plastic bag and dispose of them carefully. Don’t use the same tool on the healthy parts of the plant.
You don’t usually need to spray fungicides on the infected Verbena. The disease should subside through careful cultural practices. If necessary, spray fungicides as per suggestion.
Why are my Verbena leaves curling?
Insects like Aphids and Thrips suck the plant sap from the leaves. Such leaves curl up eventually as they’re devoured slowly by these insect pests.
Aphids are usually the reason for curling in Verbena. Snowball aphids are bluish-grey pests and are the common enemies of Verbena.
Aphids suck the plant sap from the tender leaves causing the foliage to wilt and curl. One can find them as a cluster on the undersides of the leaves.
Thrips are tiny insects that cause aphid-like damage to Verbena. Thrips aren’t that easily visible thanks to their size. You may need a magnifying glass to identify them on Verbena.
Tips to control Aphids/Thrips on Verbena
Follow the below measures to control Aphid/Thrip populations on your Verbena plants.
- You can control Aphids/Thrips on Verbena by spraying Insecticidal soap/Horticulture oil on the affected branches. Make sure to cover both sides of the leaves.
- Don’t spray Insecticidal soap when there’s direct sunlight/temperature is above 85F.
- You may want to introduce Ladybugs, Lacewings, and Parasitic wasps into your garden to control such insect pests biologically.
Tiny black bugs on Verbena
The tiny black bugs you see on Verbena are Leafminers. Leafminers are not known to kill a Verbena plant but they can cause considerable damage.
Leafminer is black with a yellow stripe on the body and clear wings. Leafminers lay eggs on the undersides of the leaves which then hatch into larvae.
These larvae feed on the foliage tissue of Verbena. Leafminer infestation is not fatal to Verbena, it just causes premature defoliation.
Introduce ladybugs onto the infested Verbena to control the insect populations biologically. Cut off the affected leaves to prevent future infestations.
Are there any weeds around Verbena?
Weeds compete with Verbena for light, space, and other crucial resources. This could weaken Verbena and sometimes could lead to fatality.
Weeds also act as a hideout for a variety of pests that infest Verbena. Weeds also provide food resources to such pests.
Clear the planting bed of weeds before planting your Verbena. Regular removal of weeds throughout the growing season is crucial.
You can also add a layer of mulch to help Verbena thrive. The layer of mulch deters the growth of weeds.
Happy Gardening 🙂