Indoor Gardening Step By Step Guide: How To Germinate Seeds Indoors

Alright, you want to grow your own plants. You’re not alone in this desire. So many people are trying to figure out how to start seeds indoors. It’s understandable why: indoor gardening is a wonderful way to get the benefits of fresh produce year-round without having to do all the work of maintaining an outdoor garden.

It also provides a great opportunity for those who live in apartments or condos where they don’t have access to green space outside their home or those who lack the time and space for an outdoor garden but still want that homegrown quality from their food.

The process of germinating seeds at home can be a daunting task. How do you know when to water them? Before moving into a bigger pot, how long should they stay in the soil? What kind of soil do I use? This blog post will answer all those questions and more in this guide!

Germination process – step by step

Here is a step-by-step germinating process to help you get started!

1. Before you begin

Choosing to germinate your seeds indoors can be tricky, but with a few key tips, you can start the process on the right foot.

When starting out, many growers get hung up on whether they should grow from seeds or clones. Some decisions are made for you (if we don’t have access to a mother plant), so the choice may be limited to one germination method.

Once you’ve decided that you’ll be growing from seed, you’ll need to answer a couple more questions:

  • How will you pick your seeds, and where will you acquire them?
  • How will you germinate those seeds?

If you’ve decided to start seeds indoors, you’ll need to make a few more decisions before commencing your growth, meaning the specific type of plant seedlings you want to cultivate and how you’ll acquire the right seeds.

When you’re ready to acquire seeds, a couple of options are available. One option involves ordering from an online seed bank. Another option is to obtain seeds from a local garden center if there are any in your area.

If you are starting with seeds that have been stored for long periods of time (more than a year), it is best to give them plenty of time since they may not be viable.

2. Setup the right environment

setup the right seedling environment

When starting seeds indoors, there are a few other considerations to keep in mind.

For instance, the air circulation and room temperature need to be monitored closely for at least three days after planting if the seeds are started indoors because they can dry out quickly.

To germinate properly, seeds need to have a temperature between 70 and 80°F (21-27°C) with no more than 16 hours of darkness and enough room to grow roots.

If your seed packet does not list the expected germination timeline, the following guidelines can help:

How much time does a seed take to germinate usually?

The time it takes most seeds to germinate varies and is determined by the type of plant, seed, and environmental factors. The most common length for germination is between two days to a week, with some seeds taking up to six months – so it’s important not to give up hope just yet!

3. Prepare the potting soil

Find suitable growing containers or seed trays to sow seeds in. I recommend using a seed starting tray, an inexpensive clear plastic tray with small holes that allows you to water and keep the soil moist without any root disturbance for each new seedling as it emerges.

Use fresh potting mix or good quality seed starting mix for transplanting. Do not reuse potting soil or use cold soil. This will provide a better foundation for starting seeds and reduce the risk of dampening off disease later on in their life cycle (see what happens if you don’t use quality dirt)

Fill a pot with moist, quality seed starting mix and use your finger to make little indentations on the surface that are big enough for each seed.

Note about soil mixture: 

There are different types of soil mixes. You want to use a quality seed starting mix, not potting soil. Potting mixes are usually lighter and have more air in them.

Potting soils will be heavier, so they don’t dry out as quickly but they may also contain weed seeds. This is why you need to get a good quality seed starting mix that has been sterilized for just this reason (see what happens if you don’t use quality dirt)

A Sterile Seed Starting Mix can be used to avoid problems up front.

Can you put seeds straight into the soil?

you can put seeds straight into the soil

Yes, you can put seeds straight into the soil. However, if there are any uncertainties about the quality of your dirt and what fertilizers have been used on it in recent months or years, planting them first in a seed tray will give you some time to examine the problem.

With seed trays, you’ll see whether there is too much clay (which stunts root growth), too much sand (which causes air pockets that block water absorption), or insufficient organic material for microbes that break down nutrients like nitrogen and phosphorus from other sources.

That said, direct sowing may work well with certain types of potting soils like Soilless Mix, Mel’s Mix, or the lighter types of potting mixes sold in stores.

Finally, direct sow gives you the benefit of growing healthy transplants adapted to your specific conditions and more resistant to plant diseases like powdery mildew.

Normally, it will be challenging if you do not use quality dirt, and water can’t get into it.

4. Start Planting

Put one or two seeds per hole and gently push them into the holes about an inch, so they’re covered by soil – not too deep!

Depending on the seed requirements, you should cover the seed with a thin layer of growing media, a deep layer, or no cover

Check the back of the packet for information about how deep to plant seeds. Use a pencil or thin object to make a shallow hole, then drop in your seed.

If you’re sowing more than one at once, space them evenly apart so they have room to grow. 

Should seeds be soaked before planting?

Some seeds require a period of soaking before you sow them. This usually occurs overnight and helps get the seed to germinate quickly.

If you know your seeds are not ready for soaking, skip step four! (skip this paragraph) If they’re soaked or pre-sprouted – go ahead and plant them now!

5. Don’t forget to feed your young seedlings

Now is when many people choose to water their container – but don’t over-water and soak the entire tray because that can cause problems too!

Add something as simple as pebbles to your potting mix if you need extra moisture between watering sessions. That should do the trick.

I recommend a water-soluble half-strength fertilizer to be sprayed in the soil weekly, which will help seedlings grow strong!

If you want some added feeding for less money (but not as many nutrients), try mixing in compost or worm-casting tea once every few weeks.

That’s it – all setup and ready to go! You’re almost there! Now, wait until they germinate into their new home 🙂

Remember when watering: never let the soil dry! Keep the container soil moist and well-drained by placing just enough potting mix into the bottom few inches, so there are ample drainage channels between all surfaces touching any standing water. This prevents soggy soil and roots that are prone to rot.

How often should I water seeds for germination?

The general recommendation is to water seeds for germination as often and deeply as they need to maintain consistent moisture. If you’re unsure whether or not to water, you can tell by feeling the top of your soil with your finger – if it feels dry, give them some more!

If you’ve been keeping a close eye on how much light they’re receiving, note any significant changes in the length of daylight for that time of year and adjust your watering accordingly. 

6. Do seeds need light to germinate?

Some seeds sprout in complete darkness, but for others, light is an absolute requirement for sprouting. If your seed requires a dark environment to germinate, consider placing it on the top of the soil or inside a sealable baggie with no light at all – this will provide them with all they need.

If you’re going to use natural light for plants that require it during growth, place the pots near an east-facing sunny window where they’ll be getting plenty of sun exposure without burning up too fast.

Fluorescent lights make excellent artificial substitutes for those with limited indoor time and space! However, many people find that exposing their plants to standard household lighting (specifically daylight) provides more than enough brightness necessary for healthy seedlings’ growth.

Do seeds need direct sunlight to germinate?

Direct sun is not necessary for seeds to germinate, but it does help seedlings grow.

If you want the best chance of your seeds successfully coming up and making a healthy green plant from what they are, place them in an area that gets natural light or other suitable lighting sources. If no direct light is available, use fluorescent lights when needed.

Do some seeds germinate better in the dark?

No, seeds need light to germinate. Seeds planted in the dark will often not come up because they do not have any natural source of visible light or other suitable lighting sources available for them to use.

If you want your plants to grow as best as possible and produce fruit, place them in an area close enough so that there is some direct sunlight, but it does not get too hot at all times.”

Most people like placing their seedling pot somewhere near a window to enjoy the fresh air coming through while still getting plenty of good quality sunshine from outside during daylight hours if it’s warm enough out and on fall/winter days. If you’re having trouble deciding on which spot would be best,

If I’m using grow lights indoors, is there anything special I need to know?

Grow lights are necessary for germinating seeds indoors during long winter months when natural light might be too weak for adequate growth. 

Artificial light provides specific wavelengths corresponding with photosynthesis – which means more energy available per photon, hence why they’re also called supplemental lighting or artificial light! Just make sure you choose the right wattage fixture type depending on how many plants you will have. 

For a more in-depth post on plants seeds that need light to germinate and those who are not.

7. Move seedlings to containers gradually

move seedlings to containers

After your seeds have sprouted, you must find a place for them. We will start moving their seedlings from a pot into a larger container. 

This process is especially important for those seeds that need to be planted in the ground soon, as they may have outgrown some small pots. But if you plan to grow vegetables indoors, you should start them in a larger pot.

For those of you new to starting seeds indoors, it’s not too complicated. You’ll need to ensure that your starting seeds have plenty of room for root growth.

If you’re unsure about how much space your plants need, check with the plant’s label or do an online search before transplant seedlings so that there are no problems later on.

Now let’s go over what kind of containers work best and why:

  • Seedling Pots – These come in various sizes, depending on how quickly you want to watch your little sprouts grow! When starting with this type of container, ensure it has big drain holes around the bottom because water can remain in the bottom and rot your seedlings. Seedling pots are also great because they have little holes on the side, allowing air circulation, which benefits any plant.
  • Clay Pots – These work well because clay holds moisture really nicely. You can take a pot like this, fill it with water, then let it sit overnight before using it again! For example: if you need to leave town suddenly after sowing seeds but forgot to water them first, just put them into a clay container, and when you get back home, all those thirsty plants will be taken care of! Remember that clay pots, like terracotta pots, tend to develop mold growth.
  • Pots with Drainage Holes – These are great because they have holes on the bottom that allow water to flow out. This is especially helpful if you’re growing plants from seeds that need to be watered daily.
  • Pots without Drainage Holes – These are great because they don’t need to be watered as often. This is especially helpful for herbs and flowers, which typically only need a drink once or twice a week!
  • Clear Plastic Cups – These are great because they let you see when the seeds have grown roots
  • Bags with Cellophane Lids – You can fill these up with dirt, then plant your seed inside them; after it sprouts, just cut off the top, and voilà! A self-watering pot!
  • Plastic Containers – If this sounds like something you want to try, use containers made of plastic rather than clay as they won’t dry out as quickly

Depending on the type of plant you are trying to grow, you’ll want different containers.

Other Frequently Asked Questions about Seed Starting Indoors

Only one-quarter of my seeds germinated. What went wrong?

The most common reasons for failure to start seeds are neglecting them, having a poor quality seed or soil, and not watering them enough.

Hopefully, your other seeds will have better luck! If you think one of these issues might be happening with your current batch, try giving it more light, cooler temperatures, or a different soil mix.

If none of those things work, then, unfortunately, nothing can be done; remember, next time take care of your plant from the beginning!

My seedlings were growing well until, all of a sudden, they toppled over at the base. What happened?

This could be due to several reasons, including the plant being diseased or infested; it became too root-bound in its pot and started to suffocate from lack of oxygen.

The stem may have been damaged by insects feeding on the leaves, which led them down into the soil. You should look for signs of pests or disease in your vulnerable seedlings.

Mold is growing on the top of the soil surface. It doesn’t appear to hurt my plants, but should I be concerned?

Mold is a natural part of the process that helps break down organic matter and release nutrients for new plants. But some molds can produce mycotoxins, which may harm humans or animals.

Therefore, you should carefully dispose of the moldy soil by shaking it out into an old pot or trash bag and then put in the garbage outside (don’t compost).

Another cause could be too much water around your roots. You need to provide plenty of drainages so that excess moisture doesn’t accumulate on top of the soil surface. Make sure no pots touch each other because this hinders airflow and allows stagnant air pockets to form where water collects.

If you’re still experiencing the problem, it may be from a lack of light. If your seedlings are in an area that doesn’t receive much sunlight or is shaded, they will need to be moved closer to photosynthesize and grow properly.

In summary: don’t overcrowd pots (don’t plant more than two plants close together), provide adequate water drains, and ensure sufficient lighting.

Can seeds germinate in a day?

Seeds can germinate faster, even as fast as a day, but it’s usually more accurate if you leave them as long as recommended. The seed packet should detail the length of time they need to be left before they can sprout; this will depend on the type of plant.


With all these questions answered, we hope you feel more confident about sowing seeds indoors. If you’re still unsure what type of soil to use or when the best time is to water them, don’t worry!

We have handy guides that answer those and many other common seed-germination queries. Congratulations on taking the first step towards sustainable living by indoor sowing some seeds today!

Photo of author
Passionate about urban gardening, indoor growing solutions, and sustainability. Believes in growing our own food and eat fresh and better food by getting back to basics, growing a fruit and vegetable garden, and cooking from scratch.

Leave a Comment