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Learning how to build a DIY Indoor mason jar garden that works(not just looks good for the cameras), may be just the sort of hands-on gardening project you’ve been searching for.
Anyone can build a mason jar garden that works, all they have to do is follow a few simple steps(which we share further on, feel free to swipe on down there now if you like!).
But, first, you need to fully understand what exactly an indoor mason jar garden is and how it differs from other types of indoor gardens.
Mason jar gardening indoors isn’t for everyone. If you think you’ve got what it takes, read on below and discover everything you need to know about getting started.
Can You Grow Plants in Mason Jars?
Growing plants in mason jars are a great alternative to buying expensive flower pots and containers for plants.
There is very little difference between growing a plant in a mason jar and growing a plant in a “regular” plant pot.
The biggest difference is that mason jar mouths are much more narrow than the wide rims of most pots and containers.
Can You Plant Seeds in Mason Jars?
Planting seeds in mason jars is a common practice for mason jar gardeners.
That said, the top layer of the jar’s contents should be kept evenly moist, and, depending on what sort of seeds you planted, they should either be placed directly under grow lights immediately, or set to the side in a dark corner for a few days.
We recently planted some lettuce and chive seeds in mason jars ourselves and they turned out just as good if not better than seeds we planted at the same time in regular seed starting containers.
What Plants Can You Grow in Mason Jar Gardens?
Believe it or not, you can grow just about any plant in mason jars that you can grow in any other container.
That’s right, most small root vegetables, leafy greens, herbs, flowers, and even house plants grow in mason jar gardens.
Some of the most popular plant species to grow in jars include:
- Swiss chard
- Fountain grass
Keep in mind, the above list is just a smattering of the many plants that you can grow in your mason jar garden.
How To Build a DIY Indoor Mason Jar Garden That REALLY Works
Building a DIY indoor mason jar garden isn’t nearly as hard as you might guess. When it comes right down to it, there isn’t much difference between growing stuff in containers indoors and having a mason jar garden.
Follow the simple steps below to make a DIY indoor garden of your own, from mason jars:
1. Gather The Needed Supplies for a Mason Jar Garden
Not all mason jar gardens are made the same, meaning there are no hard and fast rules to follow. So, after you decide on the design you want to build, gather the needed supplies. Before moving forward, double-check that everything is there(and actually usable).
2. Prepare and Sanatilze the Jars and LECA/Pebbles
Once you’ve got a plan, and all your supplies are gathered, the next step is sanitizing everything. That way, you don’t have to worry about transferring bacteria or soilborne disease from outdoors to your new indoor garden.
Boil your mason jars and scrub them with soapy water. Likewise, thoroughly rinse your LECA/pebbles and consider boiling them for several minutes as well.
Only when you’ve made sure everything is sterilized and ready for use should you start filling the jars with the materials you’ve gathered.
3. Add Sand to the Bottom of the Jars
The first layer of your mason jar garden containers is fine sand. Add a few spoonfuls, eyeballing the bottom of the jar as you go. Stop adding sand once you have a centimeter or two accumulated in the jar.
When the water reaches the bottom of the jar and turns it darker than usual, you know you’ve thoroughly watered the growing mediums in the container.
4. Add a Layer of LECA Over the Sand
The second layer of substrate for your mason jars is LECA, or pebbles/river rocks if you don’t have access to LECA. Add a layer that’s two to three times thicker than the amount of sand you added.
When water visibly leaks down through the LECA and into the sand below, you’ve either watered thoroughly enough to soak everything nicely, or you’ve overwatered.
5. Fill the Jar with Plenty of Potting Soil
The third layer to your DIY mason jars is soil, preferably rich and organic moist potting soil. That said, just about any type of potting soil will do the trick.
Avoid packing the soil into the jars forcibly, rather pour it in and shake the jar lightly. Tapping the side of the jar helps as well, just don’t knock on it too hard or you may compact the soil inside.
6. Plant Seeds in all Your Jars and Water Them
Once you’ve set up your jars with the proper layers of growing mediums and substrates, it’s time to plant seeds. If you’ve done multiple jars, it’s also a good time to add labels to the jars as you go.
That way you know what’s what in case the order of the jars gets mixed up.
The proper depth to plant seeds in mason jars ranges from barely a centimeter on up to as much as a few inches, depending on the plant species.
When your seeds are all in place, water them thoroughly. It’s best to use a spray bottle and avoid disrupting the surface layer of the soil. If you pour water, do so carefully as to not disturb the seeds.
If you displace the seeds too much, you need to replant them immediately.
7. Place the Jars Under Lights to Germinate
Now that your jars are completed, along with seeds planted, place them under grow lights that have UV rays, or in a proper windowsill.
What is a proper windowsill? That depends on the plant species you are trying to germinate/grow.
Your best bet, however, is placing your mason jars in a grow tent/grow room with plenty of light and airflow.
8. Increase the Amount of Light to Proper Levels
After your seeds germinate in their jars and begin to unfurl their true leaves, you need to increase the amount/type of light they’re receiving.
In the picture above, we’re cranking up the dimmer on our SF1000 from Spider Farmer. It’s a perfect light for just about any type of indoor gardening purpose.
If you’re interested in learning more about this light, you can read our SF1000 review.
9. Maintain Your Mason Jars Garden Daily/Weekly
Your plants are going to keep growing until they are ready for harvesting if you’re taking care of them. You have to make sure they get enough water, light, and airflow every day.
Further, you need to keep an eye out for pests, sick plants, bacteria/mold, and any other issues that might pop up.
It also doesn’t hurt to make a habit of sweeping/cleaning and tidying up the area each day/week.
10. Thin Out/Transplant Extra Plants as Needed
Long before it’s time to harvest, a week or two after your seedlings burst through the soil, you need to thin out extra plants for transplanting. If you don’t have any desire to transplant them, you can throw them away… but, they still need to be thinned out.
Failure to thin out your mason jars means the plants growing in each one will have to compete with each other for food, water, and even light. In other words, they’ll all suffer and you end up with nothing much of a harvest.
In the picture above, we thinned out our jars and transplanted the extra lettuce plants into regular black gardening containers. Now they’re growing under the same light but will have plenty of space to grow into edible crops.
11. Revitalize Soil Health as Needed
Depending on what you’re growing, how much you fertilize it, the quality of the soil, and how long you’ve been using the soil, you’re going to need to revitalize it from time to time.
In the picture above, we added some rich compost with lots of peat and broken-down wood chips, soaked with a nutrient solution, to the tops of our current indoor mason jar garden.
If you’re using your mason jars for multiple growing seasons, you are better off replacing the majority of the soil a couple of times per year than continuing to revitalize it with nutrients.
Tips for DIY Mason Jar Gardens
Starting now is better than waiting around for “better” supplies when it comes to a simple DIY indoor garden. We learned that you can work with what you’ve got if you really want to… and anyone can!
A few of the most crucial tips we learned along the way while building and maintaining our DIY indoor mason jar garden are:
- Use a spray bottle to water the plants versus pouring water
- Misting the soil with a nutrient solution regularly helps
- Medium size jars work the best for most indoor plants
- Sand and LECA layers take away the guesswork about water levels
- Provide plenty of light, whether natural or from grow lights
- If at first, you don’t succeed, try and try again
FAQS About DIY Indoor Mason Jar Gardens
What Flowers Grow in Jar Gardens?
Most flowers that are sewn by seed grow just fine in mason jar gardens. Further, even bulbous flowers grow well in mason jars, though space is limited. Lilies, daisies, and geraniums are among the most common species found in flower jars.
What Herbs Grow in Jar Gardens?
Most herbs grow in mason jars without issue. That said, don’t expect 2 or 3 foot wide and tall rosemary or thyme bushes. Mint, parsley, and basil are among the most popular herbs for jar gardens.
Are Mason Jars Big Enough for Real Gardening?
Are garden shovels big enough for real shoveling? Of course, they are! They simply don’t function on the same level as a larger-scale shovel. And so it is with mason jar gardens; they are big enough for gardening but aren’t nearly the size of a big garden.
Building a DIY indoor mason jar garden is fun and rewarding if you enjoy growing things as much as we do! Sure, you don’t have the same sort of space as you do outdoors, but they are an excellent alternative to outdoor gardening nonetheless.
If you put a bunch of them together under several grow lights, the sky’s the limit as to what all you can grow and harvest from mason jars!
Thanks for reading! We hope our article helps you build the perfect indoor mason jar garden for you!
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