Once you’ve decided to start some of your seeds indoors, you’ll want to get together a plan for what comes next. In this getting started guide for starting seeds indoors, we'll cover:
- Planning
- Choosing your growing medium and soil
- Sowing seeds
- Watering tips
- Lighting tips
- Labeling
- Fertilizer - How and when to use
- Potting up
Tips for Starting Seeds Indoors
Planning
Planning is always your first step. Do you have a good space to start your seeds indoors? Some people have an extra room that they can dedicate to their new plants inside, while others start theirs out in a shed outside or in the garage. Make sure you’ve got plenty of room for your seeds and that you can keep them warm and sheltered. Consider how many outlets you’ll need for grow lights and heating pads, and how often you’ll be able to check on your plants.
Choose your growing medium & soil
Your seeds need a growing medium with a fine and loose texture that drains well.
Do not be tempted to reuse potting medium or to use soil from outside.
The indoor sprouting environment is also perfect for fungi and other diseases to flourish. Using a fresh soilless medium that you mix yourself or buy prepared ahead of time is easy and protects your seedlings from this danger.
You’ll also want to make sure your containers are sterilized if you’re reusing them for the same reasons.
Make Your Own Seed Starting Mix
Preparing your growing medium and sowing seeds
Moisten your chosen growing medium and fill your containers evenly. If using a flat, creating rows can keep the seedlings organized.
Plants that need to be planted more deeply will benefit from being grown in individual containers or cells.
Sow your seeds spaced out uniformly according to the instructions on your packages. Different seeds have different depth requirements, so make sure you give each seed the individualized attention it deserves.
Choose Reliable Heirloom Seeds
Watering tips
Water your seeds by misting them gently. A bottom watering system can be a useful way to keep the growing medium moist without washing the seeds away.
Whatever system you choose, make sure your seeds and soil are watered evenly and never fully saturated or waterlogged.
Place a humidity dome over your seeds to keep them appropriately moist for longer. Never place domed plants in direct sunlight. Keep an eye on your seeds and pull that dome off once they’ve sprouted to prevent damping off. Water according to the needs of each seed.
Lighting tips
Provide your seeds with the light and warmth they need to germinate properly. Heating mats and grow lights give your plants a head start on the growing season. Different seeds have different heat requirements, so make sure you take the time to make sure each heating pad is set to the right temperature for optimum germination.
Label your seeds
Don't forget to label each container so you know what you’re growing. Note plant variety and date planted on labels. Using the seed packets can help you to remember the needs of each plant in case you forget.
You’ll also want to date your seeds so you remember when you planted them. This will help you keep an eye on germination and make sure that everything is on track.
Give your young plants fertilizer
After seeds have germinated, they will need some fertilizer. Soilless mediums typically are devoid of any nutrients for the young seeds. Young tender seedlings can easily be damaged by too much fertilizer, so be careful.
Use half-strength fertilizer a few days after germination and watch your plants. After they are more established, you can follow the recommended schedule of your chosen fertilizer.
Pot up as needed
As your seedlings grow, you may have to “pot them up” or move them to a bigger container to give them more room to grow even before they’re ready to move outside. A larger container will allow the plant’s roots more room to grow without becoming rootbound or drying out.
How often you have to pot up depends on the size container you originally planted your seeds in, the type of plant, and how fast it grows.
Enjoy watching your seedlings grow from tiny seeds to thriving plants. As they grow, thin out your seeds as needed to give the strongest plants more room. It won’t be long until you’re hardening them off to move outside for the next stage in their life cycle!
Written by Teresa Chandler
How to Start Seeds Indoors: The Complete Guide
Hardening Off Plants: Toughen Up Your Babies for the Real World
FAQs
1 - Herbs.
All you need is a sunny windowsill. Try basil, mint and parsley for your indoor herb garden. Check out our Italian collection of seeds for all the Italian cooking favorites. For the easiest herb growing, use our indoor herb garden kit.
How do you start seeds indoors for beginners? ›
How to Start Seeds Indoors in 4 Easy Steps
- Fill a large bowl with seed-starting mix and mix in a little water to evenly moisten the soil. ...
- Place your seed tray inside the drip tray and fill each cell to just below the top with soil.
- Sow your seeds. ...
- Cover the tray and place it under your lights on the heat mat.
1 - Herbs.
All you need is a sunny windowsill. Try basil, mint and parsley for your indoor herb garden. Check out our Italian collection of seeds for all the Italian cooking favorites. For the easiest herb growing, use our indoor herb garden kit.
What is the best soil for starting seeds indoors? ›
Commercial seed-starting mixes, usually composed of vermiculite and peat, without any true soil, are recommended for starting seeds. They're sterile, lightweight and free from weed seeds, with a texture and porosity especially suited to the needs of germinating seeds and tiny seedlings.
What is the best light for starting seeds indoors? ›
According to Pilarchik, any white LED shop lights with a brightness of 5,000 lumens or higher and a color temperature of 5,000 K or higher—like the Hyper Tough shop light—can be used as grow lights for seedlings.
What month do you start seeds indoors? ›
Planting seeds is also a great way to grow specific varieties. March is a great time to start seedlings indoors. Generally, start planting seeds indoors 6-10 weeks before the last frost date.
Can I use egg cartons to start seeds? ›
Seeds can grow in just about anything that holds soil and allows for proper drainage. Using cardboard egg cartons is a great option because they are biodegradable, and you likely have a carton already in your fridge. Plus, starting your seeds in cardboard egg cartons is easy!
What is the most difficult seed to grow? ›
Some seeds like Allium 'Purple Sensation' and Eryngium giganteum need a long period of cold-moist stratification with alternating temperatures. These are the most difficult seeds to germinate.
Which seed grow fast in 3 days? ›
Okra seeds germinate in 3-4 days time and an Okra plant has a lifespan of 6 months. The height of this plant can reach up to 2 meters. Therefore, it is important to make sure that you have adequate space prior to planting Okra. It is a nutritious food with many health benefits.
Can I plant seeds directly in potting soil? ›
Although potting soils may be used to start seeds, they tend to have a more coarse texture and may contain field soil, compost or composted manure along with vermiculite, peat moss or perlite. Some seed-starting or potting mixes may contain fertilizer as an additive.
The coarser texture of the potting soil or the garden soil may inhibit growth by not providing the correct amount of continuous moisture. However, after the tomato plants grow into healthy young plants, say in a seed starting soilless mix, you can then start transplanting your seeds into your choice of potting soils.
Can you put seeds straight into soil indoors? ›
Start these seeds indoors. Other heat-loving crops, such as pumpkin, squash, cucumber, beans and melons, thrive when direct-sown after all danger of frost is past. Some flowers, including Sweet Pea, Larkspur and Bachelor's Buttons, germinate best in cool soil and should be direct-sown early in the growing season.
How long should the light be on for starting seeds indoors? ›
Most seeds need a minimum of 14-16 hours of light per day to germinate and grow. Shop lights are a great option because they can be left on for long periods of time without generating too much heat but just enough for the plant needs.
What equipment do I need to start seeds indoors? ›
The first thing you need to get started is something to put your seeds in. You'll want to find something sterile with appropriate drainage. Plug trays and plastic cell packs are an inexpensive option that will fit easily into a tray to keep plants organized. Small individual containers can also be used, like peat pots.
Do I need grow lights to start seeds indoors? ›
The natural light from a window is seldom enough for good, strong seedling growth. They will usually stretch and lean towards the light and will not produce sturdy plants. Sowing seeds indoors under fluorescent lights is the easiest way for the home gardener to control growing conditions and grow healthy transplants.
How many seeds do I put in each hole? ›
A pencil is a handy tool to make a hole and determine the correct depth. You can measure the point of the pencil ahead of time to denote a quarter or half inch. Place your seeds in the hole and bury them. Usually, you want to plant two or three seeds per hole because not every seed will germinate.
How do you plant seeds for the first time? ›
Check seed package for planting depth.
- Make shallow indentations in the media and sow the seed evenly.
- Lightly water the surface, and place the container in a warm area (not in direct sunlight).
- As seeds germinate, move seedlings to a well-lit area, such as under fluorescent lights.
