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5 Reasons Why You Should Wait to Start Seeds

We know, as January ends, spring feels like it’s just around the corner—but the thing is, it’s not. Unless you live somewhere tropical or you have a garden in the Southern Hemisphere, starting your seeds now could cause you a lot of problems in a month or two.

Maybe your Seeds ‘n Such seeds just arrived in the mail and you can’t wait to try some brand-new varieties. Or, you can already taste that first tomato and you’re hoping to have an early crop this year. Whatever your temptation, know that starting seeds too soon does more damage than good. 

Some seeds do well in the colder, darker late winter days–including lettuce, onions, hardy brassicas, and seeds that are slow to germinate, like hot peppers and celery. But your tomatoes (and especially your squash) may not need as much time as you think.

Starting seeds too early can make more work for you in the long run. Lesser light levels and a lack of space can cause enough stress on seedlings, but add premature pest and disease problems to the mix and you have a recipe for unhealthy plants that need more attention and resources. 

Keep reading for guidance on how to figure out the perfect time to sow seeds. Should you veer on the side of starting seeds ever so slightly early, we'll touch on how to use grow lights to help prevent seedlings from becoming leggy in the first place.

5 reasons to avoid starting seeds too early

As tempting as it is to pull out the seed-starting mix on the first 60-degree day in January, you aren’t doing yourself any favors. We hope we can hurry spring along by putting on gloves and digging in the dirt, but the reality is that the earth will take the time it takes to warm—and you don't want to risk your entire spring garden to a late and unexpected frost. 

What are the consequences of starting seeds too early? There are a few:

1. Lesser light

Here in the northern hemisphere, our winters are characterized by shorter days with less intense light. Even if you can keep your seedlings warm enough, less light can stunt seedling growth or trick photoperiodic plants (like onions) into flowering prematurely. 

Indirect light has the added consequence of making “leggy” seedlings, or seedlings with spindly stems. These seedlings stretch toward whatever light source they can find, growing long but weak stems that are impossible to correct. When the time finally comes to be translated outdoors, leggy seedlings struggle to thrive.

2. Rootbound seedlings

Planted too early in the year, seedlings can outgrow their pots before it's time to transplant them outside. This leads to rootbound seedlings—when roots become so tightly confined in a container that growth is stunted. Tightly wound roots displace soil in the pot, making it harder for seedlings to get the water and nutrients they need. 

In the right environment, seedlings grow fast, quickly outgrowing seed trays and four-inch pots. If you aren’t careful you might find yourself having to repot seedlings several times, to the point that you end up with a fully grown plant that is more than ready to go outside.

3. Stressed seedlings

Lack of adequate light and colder-than-normal temperatures can result in stressed seedlings that may not grow as large or produce as abundant yields as they could have. Stressed seedlings are also more likely to suffer from transplant shock when they do finally transition to the outside garden. Between stunted growth and premature bolting, you lose any time you might have saved by starting seeds early.  

4. Pest and disease problems

Starting seeds too early may expose the young plants to pests and diseases that thrive in cooler temperatures. As every gardener knows, a pest invasion can get out of control quickly in an indoor garden and require extra effort to control and eradicate.

Seedlings that are already stressed are at a much higher risk for diseases and pests since the plants’ natural immunity is weakened. The best way to protect plants from these pressures is to start them at the right time and provide them with the ideal resources and growing conditions that they need to thrive. 

5. Increased resource usage

The larger seedlings get, the more resources they need, including water, light, and fertilizer. If you’ve started seeds before, you already know that once you sow seeds, you’re on the clock. Make sure that you’re ready to give seedlings the care they need before sowing the first round of seeds, and remember that the longer the seedlings are in your greenhouse the more work you have to do to keep them alive.

Starting seeds at the right time

If February is too early to start most seeds, when is the right time?

It's crucial to research the recommended planting times for your area and the individual requirements of the seeds you plan to sow. An understanding of your local climate and plant hardiness will allow you to determine the best time to initiate sowing.

To calculate the perfect time to sow seeds, consider the average last frost date in your area and the seed's ideal germination and growth requirements. By counting backward from the last frost date and factoring in the seed's specific needs, you can pinpoint the optimum time for planting and ensure healthy growth from the start.

The ideal time to start seedlings varies based on your hardiness zone and the seeds in question.

First, you need to identify your average last frost date. Almanac has a useful resource for this—type in your zip code here and the site will create a spring and fall planting calendar based on first and last frost dates.

Next, do a little research on the specific crop you want to grow. Look for information on how many days the seeds will take to germinate, and the recommended transplant date. Take notes on how cold-hardy those immature seedlings will be—will they be able to withstand an unexpected frost? Or will you need to wait until well past the threat of freezing weather to safely transplant them outside?

Once you know your last frost date, count backward six to 12 weeks—the exact number will depend on that particular species—for an approximate seed-starting date. Mark it down on your calendar and get sowing—it’s that easy! 

Seeds you can start early 

There are a few seeds that take so long to germinate that you might want to get a jumpstart on the season by starting them in mid-February. Only start these seeds indoors, as outside temps will still be too cold for growing seedlings:

Several weeks later (early to mid-March), you can start more seeds indoors:

Tips for starting seeds early

There are a few tricks of the trade that can help ensure success with early-season seed-starting.

Use a heat mat

A heat mat and a thermostat are essential tools for starting seeds in winter and early spring. Most seeds won’t even germinate unless the soil is at a certain temperature, so pairing the thermostat with the heat mat allows you to manipulate soil temperature to the ideal range for specific crops. 

Use a humidity dome

A humidity dome does a lot more than hold in moisture—these seed tray lids also trap heat, warming the air underneath them. When used with a heat mat, humidity domes can warm seedlings by several degrees—the perfect winter seed-starting setup. Just don’t forget to vent seedlings by removing the humidity dome during the hottest part of the day. 

Use a grow light

In circumstances where natural light is limited, using grow lights can be a game-changer. Grow lights provide the necessary light intensity and duration to facilitate the healthy growth of your seedlings. 

Normally, you wouldn’t need supplemental lighting in a greenhouse, but winter is one exception. Winter days are shorter than summer days, and to get seedlings to germinate and grow you may need to add a grow light to supplement natural light.

If your seed starting area is a room in your house or a garage or shed, you should always use a grow light—windows won’t provide enough light to foster adequate seedling growth.  

In a greenhouse, opt for a water-resistant LED bulb, and wherever you grow, choose a full-spectrum light, since plants require all wavelengths to develop properly.

Take care to position the lights an appropriate distance from the seedlings (no closer than six inches, ideally eight inches to a foot from the tops of the seedlings) and adjust the grow light up as the plants grow. It’s also a good idea to put grow lights on a timer and run them during the day to mimic natural daylight.

It's better to be late than early

So, when you feel tempted to start seeds, redirect your spring fever to other essential tasks that aren’t time-dependent, like cleaning and organizing your seed-starting supplies so you’re ready to start seeds when the weather permits.

Remember, it is far better to start seeds a little late than too early. As with most things in the garden, patience and proper planning are key to success. By waiting until the right time to start seeds, you give your plants the best chance to flourish and maximize their production potential.

And when the time is right, remember to check out the Seeds 'n Such online store for a wide selection of top-tier, non-GMO seeds. It may be too early to plant seeds but it’s never too early to order them! 

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