6 Reasons Your Seeds Aren’t Sprouting

It Hasn’t Been Long Enough

Ah, patience is a virtue in life and in gardening. While some plants sprout within a week’s time—like lettuce, tomatoes, or basil—others are slow-growing. For example, carrots can take up to three weeks to germinate, as can parsley, lavender, and peppers.

“Your seed packet provides essential details, including the recommended number of weeks to start your seeds before the last frost to start seeds and the estimated ‘days to maturity’ or ‘days to flower/harvest’ after transplanting,” says Rebecca Sears, gardening expert for Ferry-Morse.

Take note of all this information before you plant so you can set reasonable expectations.

The Seeds Were Planted Too Deep

Every seed requires a different planting depth in order to thrive.

“Seeds contain everything they need to sprout in the soil and reach the outside air and light, but the first roots and sprouts are tender and small,” notes Kaleb Wyse, gardening expert and founder of Wyse Guide. “If planted too deep, they do not have enough energy to reach the outside and will die under the soil.”

Refer to the seed packet for the right depth; most seeds only need to be planted about a quarter inch under the soil.

You’re Over or Under Watering

One of the biggest reasons indoor seeds won’t germinate is because water conditions aren’t great.

“Just like every other plant out there, seeds need just the right amount of moisture,” explains Teri Valenzuela, natural science manager for Sunday. “Too much water can either suffocate seeds and encourage fungal diseases like damping off, while too little can dry them out before they even get started.” 

She says to keep soil evenly moist (but not soggy) with reverse, or bottom watering. Simply place seed trays in a shallow dish of water so moisture soaks up from below. This helps prevent overwatering while keeping the surface damp enough for seeds to germinate. 

The Temperature Is Too Cold

Light and water are crucial for germinating seeds, but don’t forget about temperature. Warmth plays a vital role in the germination process.

“If the soil temperature is too low, the seed may not understand the cue to begin sprouting,” Wyse says. “Try using a seed starting warming mat. These mats maintain a low temperature to gently warm the soil, providing the seed with the needed conditions to sprout.”

Once the seeds have sprouted, you can remove the mat.

You Used the Wrong Type of Soil

Using the wrong soil when germinating seeds indoors can create some potential issues, including poor drainage, risk of disease, or nutrient imbalance, Sears says.

Her recommendation is to use a well-draining soil mix that’s made specifically for seed starting. This allows the vulnerable seed sprouts to root and grow more efficiently.

The Seeds Were Too Old

If you’ve done all the above and waited long enough but still don’t see any sprouts, it’s possible your seeds were too old or damaged. All seeds have a shelf life, and if they go beyond their prime they’re less likely to sprout. Wyse says, “Some seeds can last for years, while others may only last a season or two. The older a seed is, the higher the chances of germination issues.” 

To check the germination rate, Wyse recommends placing 10 seeds on a damp paper towel and putting the paper towel in a zip-top bag. After a few days, observe the seeds to determine how many germinate. If only one or two seeds germinate, it indicates a 10 to 20% germination rate, suggesting that the seeds need to be replaced. You ideally want a 50% germination rate to use a batch of seeds.