Starting seeds in trays is a popular and effective way to grow your garden from scratch. However, many beginners and even more experienced gardeners can make mistakes that hinder their success. Avoiding these common pitfalls can ensure a higher germination rate and healthier seedlings. Here are the top 11 mistakes to avoid when using seed starting trays:
1. Using the Wrong Soil
One of the most common mistakes is using garden or potting soil instead of a seed starting mix. Garden soil can be too heavy and may contain pests or diseases that can harm young seedlings. A seed starting mix is specifically formulated to be light, well-draining, and pathogens-free, providing the optimal environment for seed germination.
2. Overwatering or Underwatering
Watering is important. However, be careful not to overwater or underwater. Overwatering increases the risk of fungal diseases like damping-off, while underwatering can result in the drying out of the seeds. The soil should have just the right amount of moisture and not be waterlogged. Check the moisture level regularly and adjust your watering accordingly.
3. Not Providing Enough Light
Seedlings require much light to grow strong and healthy. Insufficient light can lead to leggy, weak plants. Place seeds under grow lights or in a sunny south-facing window if you’re starting seeds indoors. Ideally, seedlings should receive 14-16 hours of light per day. A timer can help ensure they consistently get the right amount of light.
4. Incorrect Planting Depth
Planting seeds too deeply or too shallowly can affect their ability to germinate. As a general rule, seeds should be planted at a depth of about twice their width. Follow the seed packet instructions for the recommended planting depth. It’s better to plant seeds a bit shallower than too deep if in doubt.
5. Not Labeling Seed Trays
It’s easy to forget which seeds you planted where, especially if you’re starting multiple varieties. Failing to label your seed starting trays can lead to confusion later on. Use plant labels, popsicle sticks, or masking tape to mark each row or cell with the seed variety and planting date.
6. Skipping the Hardening-Off Process
Before transplanting seedlings to the garden, they need to be hardened off. This involves gradually acclimating them to outdoor conditions. Skipping this step can shock the seedlings, leading to stunted growth or death. Start by placing them outside for a few hours each day, gradually increasing the time and exposure to direct sunlight over a week or two.
7. Planting Too Many Seeds per Cell
Planting multiple seeds in each cell might be tempting to ensure germination, but overcrowding can lead to competition for resources and weak seedlings. Plant one or two seeds per cell and thin out the weaker seedlings if both germinate. This ensures each plant has enough space to grow strong roots.
8. Ignoring Temperature Requirements
Seeds have specific temperature requirements for optimal germination. The seeds may not sprout if it is extremely cold or hot. Most seeds germinate best at temperatures between 65-75°F (18-24°C). Use a heat mat to maintain a consistent temperature, especially in cooler environments.
9. Neglecting to Monitor for Pests and Diseases
Pests and diseases can still be a problem even in a controlled indoor environment. Regularly inspect your seedlings for signs of trouble, such as discolored leaves, spots, or pests like aphids. Promptly address any issues with appropriate treatments, like insecticidal soap or fungicides, to prevent them from spreading.
10. Transplanting Too Early or Too Late
Timing is essential when transplanting seedlings into the garden. Transplanting too early, when the weather is still cold, can shock the seedlings. Waiting too long can result in root-bound plants that struggle to establish themselves. Follow the seed packet instructions for the appropriate transplanting time, and ensure the seedlings have at least two sets of true leaves before moving them outdoors.
11. Neglecting Proper Air Circulation
Good air circulation helps prevent fungal diseases and promotes strong, healthy growth. Seedlings in crowded trays or areas with poor air circulation are more prone to issues like damping-off. Use a small fan to gently circulate the air around your seedlings, and avoid placing trays too close together.