Broccoli tastes best when it is fresh from the garden. Growing your own is not hard, but sometimes diseases or pests can cause problems. One of these problems is wilting. You may wonder, “Why is my broccoli plant wilting and falling over?”
There are several different reasons broccoli wilts and falls over. This guide will walk you through the identification of the problem, treating it, and preventing it.
Why is My Broccoli Plant Wilting and Falling Over?
Your broccoli plant is wilting and falling over because of one of ten problems: Sclerotinia stem rot, black rot, black leg, fusarium yellows, wirestem, damping-off, root know nematode, club root, overwatering, or lack of water. While not all of these problems can be treated, they can be prevented.
Ten Problems Causing Broccoli Plant Wilting and Falling Over
While there are many problems that cause broccoli plants to wilt and fall over, the ten most common are discussed here.
Sclerotinia stem rot (White mold) Sclerotinia sclerotiorum
Often attacking leaves first with whitish-grey lesions, white mold is actually a fungus. It causes greyish lesions on the stem.
The fungus then infects the inside of the stem, preventing water and nutrients from flowing to the leaves and head. The plant wilts and falls over.
Black rot Xanthomonas campestris pathovar campestris
Black rot is a bacterium that also starts in the leaves. Yellow V-shaped lesions start at the leaf tips and work towards the veins on the leaf.
Once it reaches the veins, it goes into the stems. When the stem is cut open, black-brown color with yellow slime. The bacterium prevents water and nutrients from going from the roots to the rest of the plant.
Black leg Phoma lingam
Black leg is a fungus that causes ash grey spots on the leaves and stems. The spots have black centers. The black spots grow and girdle the stem, causing the plant to wilt and die.
Fusarium yellows Fusarium oxysporum forma specialis conglutinans
This used to be a common disease, but most hybrids sold now are resistant to it. The fungus enters through young roots or wounds in older roots. It causes yellow leaves, wilting, stunting, twisted stems, and causes the death of seedlings.
Wirestem Rhizoctonia solani
This virus causes black-red or black rot on seedlings after germination. They usually fall over at the soil line. The seedling may stay upright, but the stem is constricted, and it cannot grow properly.
Damping-off Pythium spp.
Damping-off is caused by a fungus. Young seedlings wilt and fall over. Close inspection shows the stem rotted at the soil line. This often kills a whole tray of seedlings being grown for later transplant.
Root-knot nematode Meloidogyne spp.
A very small wormlike creature, root-knot nematodes gnaw into roots, causing galls on them. The plant does not grow properly and wilts during the day, recovering at night.
Eventually, the roots have so many galls they cannot give the plant enough water and nutrients, so it wilts and dies.
Club root Plasmodiophora brassicae
Club root is a fungal problem that looks very much like root-knot nematodes. The entire root swells instead of just having galls on it.
We associate wilting with underwatering, but overwatering can cause it too. Roots take in oxygen as well as water and nutrients.
When the roots are underwater for a long time, they cannot absorb the oxygen the plant needs, and the plant wilts and dies. Overwatering also causes the roots to rot.
Wilted broccoli plants may mean you need to water more. This is especially true in young plants or in hot weather. Seedlings need more water than older plants because the roots are not as established.
What Stages of Growth Is Broccoli Most Likely to Wilt and Fall Over?
Broccoli is most likely to wilt and fall over during the early stages of growth. Seedlings are small and sensitive. It doesn’t take much for them to wilt and fall over.
How Do You Revive a Wilted Broccoli Plant?
In most cases, once the plant has wilted and fallen over, reviving the plant is hard. If the broccoli plant is wilted from too little water, you can water the plant and it will usually recover. If overwatering is the culprit, letting the soil dry out before watering again will help.
Plants with fungal infections can be treated with a copper or sulfur fungicide. If you catch the problem early, they may survive.
If it is a virus, the plant will not recover and should be removed and placed in a trash bag, then discarded in the trash. Treating bacterium or root rot nematodes is not feasible once the broccoli plant wilts and falls over.
How Do You Prevent Wilting in Broccoli Plants?
Using a combination of cultural and chemical controls will help you prevent wilting and death in your broccoli plants.
Cultural controls are your first line of defense in preventing wilting and death in your broccoli plants. Here are some important things to do:
- Plant certified pathogen-free seed or transplants
- Plant disease and nematode-resistant varieties of broccoli
- Remove all plant and leaf debris from the soil before planting
- Keep weeds pulled
- Rotate crops so that you do not plant broccoli where you have grown any Cole crops (cabbage, cauliflower, kohlrabi, etc.) for at least a year.
- Space the broccoli plants 18 inches apart and space the rows 36 inches apart to allow proper air circulation around the plants
- Put three inches of mulch around each plant to keep pathogens in the soil from getting on the plants
Chemicals are a last resort in preventing your broccoli from wilting and falling over.
- Using a copper or sulfur fungicide can prevent fungus problems if prior crops have had them. Be sure to read and follow the label.
- If root-knot nematodes are a problem, plant marigolds around your broccoli plants when you plant them. The marigolds contain a natural substance that greatly reduces nematodes in the soil around them.
- There is no treatment for broccoli plants that have wirestem or black rot. You must prevent them by mulching and watering properly.
In conclusion, ten problems are the most common reason why broccoli plants wilt and fall over. Seedlings are at the biggest risk of having these problems and dying. Prevention of these diseases and pests works much better than having to treat the plant once they have the problems.