How to Use a Soil Blocker for Seed Starting
Learn how to use a soil blocker for a budget friendly, sustainable, low waste method of starting your own seeds at home.
You are dreaming of a lush, productive garden this year, just like you always do. You can’t wait to see ripe tomatoes and cucumbers hanging off the vine, tall sunflowers stretching to the sky, and healthy carrots waiting to be pulled from the ground.
But every year you seem to forget. Buying all those plants costs a fortune. And starting things from seeds is messy, takes forever, and requires lots of weird equipment.
But it doesn’t have to! Seed starting with soil blockers requires a small, one time investment, and you will be starting seeds year after year with no additional costs (except the seeds, of course!).
It’s easy! Let’s get started.
Watch the process
What types of seeds will this work for?
Any type! As long as you grow what you actually eat and enjoy, you’ll never regret having extra plants!
I start “typical” things like tomatoes, peppers, etc. But this this method is so budget friendly and easy, I also start seeds that are typically considered best when direct sowed. For example:
- melons
- sunflowers
- peas
- pumpkins
- spinach
- cucumbers
I have successfully transplanted all of these from indoors, even though it goes against a lot of gardening advice.
Seeds started indoors will germinate faster and better than those that are direct sowed. And if they don’t take up much room and don’t require any pots, why not give them a little head start?
Supplies you’ll need
- The soil blocker of your choice. I use the Labrooke and it’s been great.
- A potting mix specifically designed for starting seeds. This one holds its shape well and is all organic. (You can also mix up your own with this soil recipe.)
- A large dish pan or bucket for wetting down the seed starting mix
- Seeds
- A seedling tray with a cover
- A heat mat
- A grow light or a sunny spot outside
Step by step soil blocking
Wetting the soil and shaping the blocks
We begin by wetting down the seed starting mix. You want it to be very wet, so that when you squeeze it, water runs out. Let it sit for a few hours to make sure its well saturated. If you skip this step, it won’t hold together as well in the blocks.
Press the seed starting mixture into the soil blocker. Don’t worry about squeezing it out beforehand. Press it in the best you can. Water will run out as you press the soil in and that’s okay.
Forming the blocks and planting the seeds
To press out the blocks, simply push down on the top of the soil blocker. Press them directly into the seed starting tray that you are using.
They will be touching, but you will want to separate them. If the blocks are too close, they will turn into sort of a sludge when you water them. If you separate them, they will keep their shape better.
Place a seed into the little divot formed by the soil blocker. Germination rates in these tend to be very good, so if I’m using fresh seeds I just put one seed per hole. Take a little bit of the seed starting mix and cover the seed with a thin layer. Some seeds will need light to germinate and you just leave those uncovered, right in the hole.
Seeds will germinate best in a warm, humid environment. Cover them up with the plastic tray, and set it shut to keep the moisture in. Place the whole tray on a heat mat and soon you will see the magic happen.
What’s next for the seedlings?
They should germinate very quickly on a heat mat, in just a few days. Once at least half of them have germinated, remove the cover and give them light.
If you live in a mild climate, they can often go right outside. Keep the clear plastic cover on and open the holes for a little ventilation. The cover will retain heat and acts like a mini greenhouse. On warm days, remove the lid altogether, and on cold nights, bring the whole tray inside. This will produce stronger seedlings overall.
In cold or windy climates, you’ll want to keep everything indoors while the weather changes. This means you’ll need lights.
Watering and fertilizing within the soil blocker
The seedlings should not need any water the first few days since the soil mixture is so wet and the lid traps the moisture.
But at time goes on, the soil blocks with need to be watered. You never want them to completely dry out. The easiest way to water them is to just pour a cup of water into the tray. Water a small amount at a time to avoid having them fall apart.
Once the seedlings are an inch tall, you will want to add a little fertilizer into the water. You can be get liquid or powdered fertilizers specifically for seedlings. Don’t use anything at full strength, or it will be too much for them.
Transferring to the garden
Some plants, like tomatoes and peppers, will want to be transplanted into a larger container so that they can get bigger before they go into the garden. You can use old, washed out food containers, paper cups, or just about anything else that is clean and has a drainage hole.
Any smaller plant can go right for seed starting tray straight into the garden. You will want to leave the tray outside for a few days to harden off the seedlings, or get them acclimated to outside life.
Pop them right in the garden, water them well, and enjoy your harvest!
And we’re done!
I hope you find that this method of starting your seeds is so budget friendly and easy that it inspires you to start more things indoors.
Want to follow along with my garden? Follow me over on Instagram to see the latest.
By Katie Shaw
Katie lives in Virginia with her husband, three daughters, a chocolate lab, and over thirty chickens. She loves creating simple tutorials for sourdough, bread, and soap. Her recipes, articles, and YouTube videos reach millions of people per year.
