Starting seeds indoors is one of the most rewarding aspects of gardening. It allows you to grow a wider variety of plants, save money, and get a head start on the growing season. However, not all advice you hear about seed starting is good advice. In fact, some tips can lead to frustration, disappointment, and even complete failure. Over the years, I’ve encountered my fair share of bad seed-starting advice—and learned the hard way what not to do.
In this guide, I’ll share six of the worst seed-starting tips gardeners have ever heard, explain why they’re problematic, and provide better alternatives to help you succeed. Let’s dig in!
1. “Use Garden Soil for Starting Seeds—It’s Free!”
Why It’s Bad Advice
Garden soil might seem like a convenient and cost-effective option, but it’s far from ideal for seed starting. Garden soil is often too dense, which can lead to poor drainage and compaction. It may also contain weed seeds, pests, or diseases that could harm your delicate seedlings.
What to Do Instead
- Use Seed-Starting Mix: Invest in a high-quality seed-starting mix specifically formulated for germination. These mixes are lightweight, sterile, and provide excellent drainage.
- DIY Option: If you prefer making your own mix, combine equal parts peat moss (or coconut coir), perlite, and vermiculite for a well-draining blend.
2. “Plant Seeds as Deep as Possible So They Have Room to Grow”
Why It’s Bad Advice
Seeds don’t need deep planting to thrive—in fact, burying them too deeply can prevent them from sprouting altogether. Most seeds require only a thin layer of soil to anchor themselves and access light once they germinate.
What to Do Instead
- Follow Seed Packet Instructions: Each seed type has specific depth requirements listed on its packet. As a general rule, plant seeds at a depth two to three times their diameter.
- Surface Sowing: Some tiny seeds, like lettuce or petunias, need light to germinate. Simply press them gently into the surface of the soil without covering them.
3. “Water Your Seeds Every Day to Keep Them Moist”
Why It’s Bad Advice
While consistent moisture is crucial for germination, overwatering is one of the most common mistakes beginners make. Too much water can drown seeds, cause fungal issues like damping-off disease, or lead to mold growth.
What to Do Instead
- Check Moisture Levels Before Watering: Stick your finger into the soil or use a moisture meter to determine if watering is necessary.
- Bottom Watering: Place your seed trays in a shallow dish of water and let the soil absorb moisture from below. This prevents disturbing the seeds and reduces the risk of overwatering.
- Mist with a Spray Bottle: For very small seeds, misting the soil surface lightly keeps it moist without saturating it.
4. “Keep Your Seedlings on a Windowsill for Light”
Why It’s Bad Advice
While windowsills might seem like a logical spot for seedlings, they rarely provide enough consistent light for healthy growth. Natural light through a window is often insufficient, especially during shorter winter days, leading to leggy, weak seedlings.
What to Do Instead
- Use Grow Lights: Invest in full-spectrum LED or fluorescent grow lights. Position them just a few inches above your seedlings and keep them on for 12–16 hours per day.
- Rotate Regularly: If you must rely on natural light, rotate your seedlings daily to ensure even exposure and prevent them from leaning toward the light source.
5. “Thin Out Seedlings Only After They’re Big Enough to Handle”
Why It’s Bad Advice
Waiting too long to thin out seedlings creates overcrowding, which leads to competition for nutrients, water, and light. By the time you finally thin them, the remaining plants may already be stunted or stressed.
What to Do Instead
- Thin Early and Ruthlessly: Once your seedlings develop their first set of true leaves (not the initial cotyledons), thin them to the recommended spacing. Use scissors to snip off unwanted seedlings at the base instead of pulling them, which could disturb the roots of neighboring plants.
- Sow Sparingly: To reduce the need for thinning, sow seeds sparingly in each cell or container. A single seed per cell is ideal for larger seeds; for smaller ones, aim for 2–3 seeds per cell.
6. “Fertilize Right Away to Give Seedlings a Boost”
Why It’s Bad Advice
Newly sprouted seedlings don’t need fertilizer immediately—they have enough stored energy in their seed to sustain early growth. Adding fertilizer too soon can overwhelm their delicate root systems and burn the plants.
What to Do Instead
- Wait Until True Leaves Appear: Begin fertilizing only after the seedlings develop their first set of true leaves. Use a diluted, balanced liquid fertilizer (such as 10-10-10) at half strength once a week.
- Focus on Healthy Soil First: A quality seed-starting mix typically contains enough nutrients to support seedlings until they’re ready for transplanting outdoors.
Final Thoughts
Seed starting doesn’t have to be complicated, but following misguided advice can turn a simple process into a frustrating experience. By avoiding these six common pitfalls—and adopting smarter practices—you’ll give your seedlings the best possible start in life.
For me, learning how to properly start seeds was a journey filled with trial and error. But once I replaced bad habits with proven techniques, I saw dramatic improvements in my success rate. Whether you’re a beginner or a seasoned gardener, remember that patience and attention to detail are key. With the right approach, you’ll soon be nurturing strong, healthy seedlings that will flourish in your garden.
So ignore the bad advice, stick to the tried-and-true methods, and watch your seed-starting efforts pay off. Happy planting!
