Troubleshooting Problems with Seeds and Seedlings: A Guide for Vegetable Gardeners

Poor Germination Rates

One of the most frustrating problems gardeners face is poor germination rates. Several factors can contribute to this issue, including:

• Seed Quality: Always purchase high-quality seeds from reputable suppliers to ensure better germination rates.
• Seed Age or Storage:  If you’ve had the seed for more than a year and it hasn’t been stored properly (in dry, not too hot or cold conditions), germination rate can be affected.  Seed has a shelf life of up to 3 years, so check the expiry dates on your packet.
• Incorrect Planting Depth: Planting seeds too deep or too shallow can prevent them from germinating properly. Follow the instructions on the seed packet for optimal planting depth.
• Temperature and Moisture Levels: Seeds require specific temperature and moisture conditions to germinate successfully. Ensure that the soil is consistently moist but not waterlogged, and maintain the appropriate temperature for the specific vegetable seeds you’re growing.

Read our blog on how to germination test your seeds at home.

Damping Off

Damping off is a common fungal disease that affects seedlings, causing them to wilt and eventually die. To prevent damping off:

• Use sterilised seed starting mix to minimise the risk of fungal contamination.
• Provide good air circulation by spacing out seedlings and avoiding overcrowding.
• Water seedlings from the bottom to keep the soil surface dry and reduce fungal growth.

Leggy Seedlings

Leggy seedlings are tall and spindly with weak stems, often caused by insufficient light or improper growing conditions. To prevent leggy seedlings:

• Place seedlings in a location with adequate sunlight or use grow lights to provide supplemental light.
• Maintain consistent temperatures and avoid sudden temperature fluctuations.
• Transplant seedlings into larger containers if they become overcrowded, allowing them to develop stronger roots and stems.

Nutrient Deficiencies

Seedlings need a balanced supply of nutrients to grow healthy and strong. Symptoms of nutrient deficiencies may include yellowing leaves, stunted growth, and poor overall vigour. To address nutrient deficiencies:

• Use a balanced fertiliser or amend the soil with organic matter to provide essential nutrients.
• Monitor pH levels and adjust soil acidity or alkalinity as needed for optimal nutrient uptake.
• Avoid over-fertilising, as this can lead to nutrient imbalances and other problems.

Pest and Disease Issues

Seedlings are vulnerable to pests and diseases that can hinder their growth and development. Common pests include aphids, caterpillars, and flea beetles, while diseases such as powdery mildew and bacterial leaf spot can also affect seedlings. To manage pest and disease issues:

• Inspect seedlings regularly for signs of pest infestation or disease symptoms.
• Use organic pest control methods such as hand-picking pests, applying insecticidal soap, or using biological controls like ladybugs.
• Practise good garden hygiene by removing plant debris and weeds that can harbour pests and diseases.