Common seedling problems and responses

  • Leaf Curl

  • Too much fertilizer will cause leaves to curl, especially in bright light. Decrease the amount of fertilizer and if the problem is severe replant the seedling in fresh potting soil.

  • Yellowing of Lower Leaves

  • Too much fertilizer can cause leaves to yellow. Avoid over feeding young plants. Make sure there is good air circulation around the plants.

  • Leggy Plants

  • A leggy plant has large gaps or spaces between leaves and thin, weak stems. Be sure the plant is getting sufficient light. Don’t let the temperature get too high. Make sure your plants are not overcrowded. A good course of action is to transplant the leggy plant into a deeper container.

  • Leaf Discoloration

  • Discolored leaves are often a sign of nutrient deficiency. Pale leaves may be a sign of nitrogen deficiency or lack of enough light. Reddish purple undersides can be a sign of phosphorus deficiency; the seedling may also be stunted with thin, fibrous stems. When the soil is too acid, phosphorus is not taken up from the soil. Bronze or brown leaf edges can be a sign of potassium deficiency or overwatering.
    When leaf discoloration occurs, repot the seedling into a medium that contains compost. Compost is likely to contain the trace minerals plants need.

  • Discolored Roots

  • Discolored roots can be caused by overfeeding or overheating which can result in excess fertilizer salts being released into the soil. Use well aerated soil and do not overfeed or overwater.

  • Mold

  • Mold on the soil surface is a sign of poor drainage and lack of air circulation. Scratch the soil to increase aeration, move seedlings to a place with good air circulation. You can also add powdered charcoal to the soil surface.

  • Insect Damage

  • Indentify the insect at work. Prevention is always the best course of action. Avoid overfeeding which can result in excessive green growth which can attract insects such as aphids. Keep the greenhouse or garden free of plant debris which can harbor sowbugs, slugs, and snails. Place plants where there is good air circulation to slow down spider mites. Use yellow sticky traps to control whiteflies. Use blue sticky traps to control trips.

  • Damping-off

  • Withered seedlings and plant failure is a sign of the fungal disease damping-off. Damping-off attacks plant stems at the soil surface. Too much nitrogen and moisture can result in damping-off. Too little air circulation can also lead to damping-off. Prevention is the only course of action: maintain good air circulation, avoid overwatering, sow seeds in a sterile medium.

  • Poor Root Growth

  • If transplants fail to root well then several factors may be at play: poorly drained soil, insufficient soil fertility, over-fertilization, the temperature is too low, seed starting medium or soil insufficiently aerated.
    For successful production of seedling contact the expert team of Horticentar.