Have the seedling went through a period without watering or suffered a dry spell?
Did you use much fertilizer to improve the soil?
Are there any grubs or maggots present around the plant or in the soil?
Did you bought seeds from an unreliable source or used your stored old seeds?
Are the roots or stems of your seedlings rotted?
Dry soil is the most common reason for wilting and falling of the vegetable seedlings. Keep the soil evenly moist throughout your garden. You can achieve this by mulching young vegetables.
Young plants can be sensitive to fertilizer burns, so you should never use fertilizers excessively when planting vegetable seedlings. Follow fertilizer directions and mix it thoroughly with the soil.
Cutworms and root maggots are usual pests of young vegetables. Check for grubs curled in the soil at the base of plants. Keep garden clean of debris and plant residue. Keep garden weed-free. Use cardboard collars around seedlings. Use floating row covers to exclude flies and moths from laying eggs in the soil.
Unreliable sellers may sell old, diseased, or inferior quality seeds with poor seed viability. Always buy seeds from reputable nurseries or seed companies. Plant seeds packed for the current year.
Root or stem rots are fungal diseases that can infect and kill young vegetable seedlings. To prevent rots, do not overwater, let the soil surface dry a bit between waterings. Add aged compost to the soil to improve drainage. Plant only certified seed. If stem rot disease is known to present rotate crops with non-hosts such as cereals.
Damping-off is a fungal disease that causes young seedlings to wilt and fall over. To prevent damping-off let the soil surface dry between waterings, thin seedlings to avoid overcrowding and do not add nitrogen fertilizers until plants have developed leaves. Treat soil with fungicide if the disease occurs.
https://harvesttotable.com/common_vegetable_garden_proble/
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Sreten null
Hi! I’m Sreten Filipović. I graduated from the Faculty of Agriculture at the University of Belgrade, with a master's degree in Environmental Protection in Agricultural Systems. I’ve worked as a researcher at Finland's Natural Resources Institute (LUKE) on a project aimed at adapting south-western Finland to drought episodes. I founded a consulting agency in the field of environment and agriculture to help farmers who want to implement the principles of sustainability on their farms. I’m also a founding member of the nonprofit organization Ecogenesis from Belgrade whose main goal is non-formal education on the environment and ecology. In my spare time, I like to write blog posts about sustainability, the environment, animal farming, horticulture, and plant protection. I’ve also published several science-fiction short stories.
You can find me on LinkedIn at https://www.linkedin.com/in/sreten-filipovi%C4%87-515aa5158/