How To Start Seeds Indoors In Winter - Backyard Boss
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How To Start Seeds Indoors In Winter

Finally, you’ve decided to start growing your own plants from seed. It can be a lot of fun, and it’s a great way to get the kinds of plants you want in your garden without paying those nursery prices. But, there’s one little problem: weather conditions play a huge role in plants. The temperature, amount of sunlight, and rainfall all affect how your plants will grow. In the winter months, plants are less likely to develop due to limited natural lighting and colder temperatures.

Don’t worry, though – with a little bit of ingenuity, you can still start seeds indoors during the winter months. Once the weather warms up, they can be planted outside. Follow these steps, and you’ll be on your way to homegrown success!

What You’ll Need

sowing green onion seeds in plugtrays
Image credits: Manon25s via Pixabay

In order to successfully grow seeds indoors during the winter, you will need to make sure that you have all of the necessary supplies on hand.

Step-By-Step Guide to Sowing Your Seeds Indoors

If you’re looking for a way to continue growing your favorite flowers and vegetables indoors, then read on for a step-by-step guide.

Step One – Gauge Your Indoor and Outdoor Space

Organic vegetable garden greenhouse with butternut squash seedlings in potting trays and soil with white plastic label stake and defocused farm exterior background. No people with copy space.
Image credits: Mary Salen via Shutterstock

To start your seeds successfully and make sure they grow into healthy plants, it’s important to plan ahead and give yourself enough room in your indoor growing space. Also, it’s essential to keep your outdoor space in mind. You don’t want to start too many plants and then not have room in your outdoor garden once it’s time to transplant.

Sketch out an outline of your garden plot on some paper so that you have a clear idea of where each crop will go. That way, you can ensure your garden is evenly spaced and that you have enough plants to fill it.

Step Two – Choose Your Optimal Indoor Location

Rosemary seedlings
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Next on the list is choosing a good location for your seedlings. Ideally, you want a space that receives indirect light throughout the day with temperatures ranging from about 65 to 75 degrees Fahrenheit. Avoid harsh direct sunlight since this can damage tender young foliage.

Step Three – Moisten Your Starter Mix

Seed Starter Mix
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Add water to your starter mix until the mixture holds together in your hand. It should feel like a moist sponge. Let it stand for a few minutes so the moisture can be absorbed. Then stir again to make sure all of the mix is uniformly wet.

Step Four – Add Your Seed Starter Mix to Your Containers

Group of people planting seeds
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Add dampened seed starter mix to your clean, prepared tray.

Be sure to use containers that have drainage holes in the bottom. When reusing an existing tray, make sure you wash it thoroughly with hot, soapy water. If you are reusing an old container rinse it with a 10 percent bleach solution before drying it completely.

Step Five – Plant Your Seeds

Wildflower seeds
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Now that your growing container is prepped, it’s time for planting the seeds! Read through each seed packet carefully to get to know your plant. It should state how deep your seeds should be planted, how many days until germination, and what type of lighting they require. If you have mature seeds with a lesser development rate, you can sow 2 or 3 seeds at a time and thin them out later.

Step Six – Label Your Containers

Young Seedling of apple mint, Mentha suaveolens in flowerpot set in rows at garden shop.
Image credits: creativeneko via Shutterstock

By labeling your plants with the date they were planted, the type of plant, and any other important details about their growth or care, you can easily track their progress over time. This way you can ensure they get all the love and attention they need.

Step Seven- Cover With More Seed Starter Mix

pouring vermiculite from a factory package into a pot of soil to prepare a mixed soil for seed germination in the spring, adding granules to improve potting soil for seedlings at home
Image credits: Skyliz via Shutterstock

Cover your seeds with additional starter mix or horticultural vermiculite. This will help keep them moist, which is especially important since they’re still in their germination phase.

You don’t need to add any extra water at this point, as the pre-moistened soil has enough water for the seeds to start growing.

Step Eight – Cover With Plastic

Covered Seed Pods
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Cover your container with your plastic cover or clear plastic sheeting. This will help maintain humidity in the container and prevent the seeds from drying out during germination. Now, place your container in a warm location, out of direct sunlight. The ideal temperature for germination is around 75 degrees Fahrenheit.

Step Nine – Move Your Seedlings

Seedlings in containers
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Once the seedlings have sprouted, it’s important to provide them with plenty of light and warmth. Ideally, you should move them to a south-facing window or under grow lights, keeping the temperature around 65 to 70 degrees Fahrenheit. You need to provide strong sunlight.

To help ensure optimal growth and development, you should also fertilize your plants weekly, and water them lightly but enough to keep them from wilting. Remember to be mindful of your plants’ needs – avoid overwatering or giving them too much sunlight, as these can both be detrimental to their health.

Tips on Sowing Your Seeds Indoors

Watering baby cucumber plants
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One of the most important things you can do is to plant similar need seeds in the same trays. That ensures they will all germinate at roughly the same time. This not only makes it easier for you to manage your indoor garden but also allows your plants to grow and flourish together.

As your seedlings sprout, you’ll notice that they need some room to grow. That’s why it’s important to thin out the plants. Di this by leaving one plant per cell when the second set of leaves appears. Depending on how big your tray is, you can keep the plants in this stage until you’re ready to move them into your garden.

Finally, hardening off plants before putting them in the garden is a must if you want to ensure healthy and thriving plant babies. Ideally, this process should be done over the course of seven to 10 days. This will allow your plants to gradually adjust to outside temperatures, wind, and light levels so they are not suddenly shocked when you transplant them into the ground.

Plants Pending

So, you want to start growing your own plants from seed, but don’t want to wait until the spring? No problem! You can start seeds indoors during the winter months and have them planted outside by the time the weather begins to warm up.

Follow these simple steps, and you’ll be on your way to homegrown success. Share this article with your gardening friends so they can get in on the fun too!

Do you have any tips on growing seeds indoors? Leave a comment down below!