Common Mistakes Made While Growing Seeds Indoors

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Starting seeds indoors is quite economical, especially when the seedlings grow in robust plants. However, growing seedlings indoors can be a challenge as it requires more care than growing outdoors.

A few incredibly indoor seed starting mistakes may discourage you from starting your seeds. Fortunately, there are ways in which you can identify, fix and avoid these mistakes.

Here are some of the most common mistakes people make while growing seeds indoors:

Not Supplying Enough Light

One of the most common mistakes while growing seeds indoors is not providing enough light. Many people assume that they will be fine if they place their seedlings near a window. However, most windows do not provide enough light for indoor plants.

Not Supplying Enough Light
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Seedlings need a lot of light to grow into sturdy, healthy plants. No matter what anyone tells, the chances are that you don't have enough natural light in your home to grow robust seedlings. However, you can use artificial light to achieve the right light required by seedlings.

Obtain grow lights designed for plants. A more economical solution is to purchase large fluorescent shop lights outfitted with one warm bulb and one cool bulb. Suspend the lights from chains so that you can raise the lights higher as the seedlings grow.

Starting Seeds Too Early or Too Late

One of the most common mistakes people make when growing seeds is starting them too early or too late. If you start your seeds too early, they may not be ready to be transplanted outdoors when the weather is warm enough. If you start your seeds too late, they may not have time to grow large enough before the cold weather arrives.

To avoid all these, make sure you know your specific areas' last frost date. Take note of your last expected frost, count backwards and plant seeds at the proper time so they aren’t growing indoors becoming root bound before you can get them inside.

Failing to Label Seeds

To be able to identify seedlings as they grow and to know when they’ll be ready for transplanting, you should label the seed containers as you’re sowing. For every type of seed sown, use popsicle sticks or plastic plant markers and permanent ink pens to record the plant name and date sown.

Sowing Too Many Seeds

Another common mistake is sowing too many seeds. When you sow too many seeds, the plants will compete for resources and may not all survive. To avoid this, read the seed packet carefully to determine how many seeds to plant per square foot or pot. When sowing seeds, begin modesty if you're a beginner.

Sowing Too Many Seeds
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If you sow seeds that you can't reasonably maintain, nurturing the seedlings into adulthood will become challenging. Depending on the type of plant you want to grow, you might be able to sow seeds in outdoor containers or the ground when outdoor temperatures warm up.

Growing Seeds in Poor Quality Soil

Soil is one of the most important components of starting seeds indoors, and it needs to contain all the essential nutrients and biology for new sprouts to thrive. Using bad quality soil or just filling your seed trays with soil for your backyard is a recipe for a disaster.

Growing Seeds in Poor Quality Soil
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Bad quality soil can introduce harmful diseases and pests into your growing medium. Seeds grown in poor soil may not sprout, and the plant will begin its life in an already weakened state. Make sure you know how to easily make compost so you can use it to improve the quality of your soil.

Using Old Seeds

Another common mistake made while growing seeds indoors is using old seeds. Seeds have a finite shelf life and will eventually die, regardless of whether they are stored in a cool, dry place or not. Old seeds don't only germinate at lower rates, they can also have low strength and vitality as they grow.

To ensure successful germination, it is important to use fresh seeds. If you are not sure of the age of your seeds, it is best to discard them and purchase fresh seeds. Also, be sure to store your seeds in a cool, dry location. A cool, dark basement is a great choice, and the refrigerator is even better.

Using Inadequate Soil

Another common mistake made when growing seeds indoors is using inadequate soil. Soil is essential for the germination and growth of seeds, so it is important to use a good quality soil mix. Many commercial potting soils are designed for indoor use and will work well for most plants.

To germinate and grow well, seeds need lightweight, nutrient filled soil that drains well. Those tiny cells of soil are the seed's home for its first six to eight weeks of life, and that soil needs to be perfect to promote strong root growth. Never use plain garden soil or top soil to start seedlings. You can learn various DIY soil tests to make your soil better for your seeds and grown plants.

Use high quality seed starting soil with slow release nutrients. You can also easily make your own high powered potting soil right at home.

Starting Seeds in a Sunny Window

If you live in an area where the sun shines most days, you can start some of your seeds directly in the window. Just rotate the containers regularly so the plants grow evenly.

Not all plants like direct sunlight, so you will need to research what types of plants you want to grow. Also, the light from the sun through a window is too far away. And young seedlings spend too much energy growing towards it and not filling it out.

It's better to grow seeds indoors with artificial light. No need to purchase fancy and expensive equipment. Instead, ordinary fluorescent bulbs will do the trick. Place the plants close to the light, about 8-12 inches away, and turn them every few days.

Applying Too Much or Too Little Water

One of the most common mistakes while growing seeds indoors is watering them too much or too little. Overwatering can drown the plants, while underwatering will make them wilt. Overwatering can also create soggy soil that causes the roots of the newly sprouted seeds to rot.

It can also create an environment for fungal diseases to propagate and cause damping off. To determine how much water your plants need, feel the soil. It should be damp but not wet. Create a mini-greenhouse to keep the soil moist, cover the container with plastic until the seeds germinate.

Not Supplying Seeds and Seedlings With Enough Heat

Part of starting seeds indoors is to extend the gardening season and get ahead when the ground is still frozen. Soil temperatures need to be approximately 65 to 70 degrees Fahrenheit for most fruits and veggies to sprout.

Seeds and seedlings kept in cold conditions might fail to sprout. Sprouted plants will become slow growing and weak. Ensure you have designated a grow room or heated greenhouse where thermostats and humidifiers keep the heat at the optimal level for sprouting and new growth.

Keep your seedlings in a warm room of your house up high as heat rises, and they will be the warmest close to the ceiling. Heat mats are an affordable investment if you have a drafty house, as they heat the soil from below and can keep it at the optimal temperature for growth.

Not Thinning Seedlings

When planting seeds, most people make the mistake of planting them too densely. This can cause overcrowding and competition for light, water, and nutrients. As a result, the plants will be weak and less likely to survive. Depending on the germination rate contained on your seed carpet, you may want to start one or two more seeds in each cell. This helps ensure that each cell will likely have at least one seed germinate.

It can also be hard to find the balance between planting enough to account for germination failures and planting too much and having overcrowded seed trays. This may result in cramped seed trays where young seedlings compete for resources.

This creates leggy seedlings with poor airflow that are more prone to infection. Unless you're growing microgreens, you need to ensure adequate space between each plant to prevent weakening the whole tray. To avoid crowded seedlings, you should thin as early as possible by snipping away the unwanted sprouts at the soil level.

Planting Seeds at the Wrong Depth

Another common mistake made while growing seeds indoors is planting them at the wrong depth. Many people believe that you need to bury seeds deep in the soil to ensure germination, but this isn't always the case. In fact, some seeds actually need light to germinate and should be planted on the soil's surface.

Planting Seeds at the Wrong Depth
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As you already know, the seeds of different fruits and vegetables vary enormously in size and shape, and they all have different specifications for planting depth and spacing. Some flower seeds, like snapdragon or chamomile, need light to germinate and shouldn't be buried at all.

Not Providing Seedlings With Enough Air Circulation

Another common mistake made while growing seeds indoors is not providing enough air circulation. When plants don't get enough air, they can become susceptible to diseases and pests. Make sure you have plenty of holes in your containers and use a fan to circulate the air if necessary.

Applying Chemical Fertilizer to Seeds

Another common mistake is to apply chemical fertilizer to seeds. When you do this, you can damage or kill the seed. It's best to wait until the seed has germinated and has a few leaves before you start fertilizing it. Using strong fertilizers on sprouted, mature seedlings can burn their roots and do more harm than good.

As long as you have high-quality soil, moisture, space, and light, allow your seeds to do their thing. Once your seedlings are large, you can give them a boost with seaweed or kelp organic fertilizer or some good old aged compost.

Not Hardening Plants Off Before Planting Outdoors

Another common mistake made while growing seeds indoors is not hardening plants off before planting them outdoors. When plants are first transferred from a warm, controlled environment to a cooler, more natural outdoor space, they can go into shock. This is especially true for young seedlings that have not been hardened off yet.

FAQs on Common Mistakes Made While Growing Seeds Indoors

What stops seeds from sprouting indoors?

Your seeds may stop sprouting indoors because of too much or little water. Seeds need moist soil to germinate and grow their strongest. Provide steady, even moisture by watering lightly with a spray bottle or a hose on a gentle setting as often as needed to ensure the soil never dries out.

How often should you water seedlings indoors?

Watering frequency will depend on the soil, climate, and size of the container. Check the soil moisture daily by sticking your finger in the soil. If the top layer of soil feels dry, water until the soil is wet again. Avoid over-watering, which can lead to root rot.

Why didn't my seeds germinate?

There are many reasons why seeds may not germinate, but common reasons include too much or too little heat, light, or water. Make sure you are providing the correct conditions for your specific seeds and adjust accordingly. Also, be sure to use fresh, high-quality seeds that have been stored properly.

Final Thought on Common Mistakes Made While Growing Seeds Indoors

As you can see, there are common mistakes you can make while growing your seeds indoors. However, by being aware of these mistakes and taking the proper precautions, you can ensure successful seed growth. Starting your own seeds has a lot of advantages as compared to starting your seeds outdoors.


Kristina Perrin

Kristina Perrin

Kristina is an expert DIY home remodeler and mom to three. When she's not cooking or experimenting with new recipes, you can find her working on new home improvement projects or writing about her favorite kitchen appliances or DIY projects on Kitchen Infinity blog.

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