This website contains affiliate links. As an Amazon affiliate, I earn a small commission from qualifying purchases (at no cost to you).
Content Created by Tracey of Baker Street Living 
Starting seeds indoors doesn’t have to be expensive or complicated when you use these cute plastic bottle greenhouse seed starters. This simple DIY turns empty plastic water bottles into mini greenhouses that create the perfect environment for germination, warm, humid, and protected. It’s a great way to reuse materials you already have while giving your seedlings a strong start.
This method works especially well with Jiffy pots because they hold moisture nicely and make transplanting easy later. The bottle acts like a clear greenhouse dome, trapping humidity and warmth while still letting sunlight reach your seeds.
Supplies List
- Empty clear plastic water bottles
- Jiffy pots (make sure you measure the bottle to ensure fit)
- Seed starting soil
- Seeds of your choice
- Scissors or Craft knife (adult supervision recommended)
- Printable sticker paper for labels. (optional)
How to Make a Plastic Bottle Greenhouse
1. Prepare the Bottle
Start with a clean, clear plastic bottle. Water bottles and soda bottles work very well. Cut the top two-thirds off the plastic bottle. The bottom portion will become your planting base, while the top will act as the greenhouse dome.
Cut small slits into the top piece of the bottle as shown. About 3/4 to 1 inch is plenty. This allows for the top to slide onto the base.
2. Prep the Jiffy Pot
Fill a Jiffy pot with potting soil or seed-starting soil, leaving a small space at the top.
3. Plant Your Seed
Follow the planting depth instructions for your seeds. Gently press soil over the seed and add a little water.
4. Assemble the Plastic Bottle Greenhouse
Place a Jiffy pot inside the bottom section of the bottle. Place the top portion of the bottle back over the bottom by sliding the cut edge of the base. This traps humidity inside, creating a mini greenhouse.
Add a Label
Download and use our easy printable adhesive labels. Just print them on sticker paper, fill them out and stick them onto the clean bottle. Alternatively, create your own labels or attach the seed packet to the bottle for quick and easy reference.
5. Place in a Sunny Window
Set your plastic bottle greenhouse on a bright windowsill. Check moisture levels every few daysand add water as needed. The enclosed space helps retain humidity, so watering needs are minimal. If the soil is drying out too fast, place the lid on the bottle. If there is too much humidity and mould is forming on the soil, remove the top or the lid.
Transfer to the Garden
When it is time to move the plants to the garden, remove the Jiffy pot and plant them in the garden. If you find it difficult to remove the Jiffy pot from the bottle, cut down the side of the bottle to fold open the bottle for easy removal.
Tips for Success
- Watch condensation: A little moisture inside is good. If it looks overly wet, remove the dome briefly for airflow.
- Rotate occasionally: This helps seedlings grow straight toward the light.
- Remove the dome after sprouting: Once seedlings are strong and leaves appear, gradually introduce fresh air.
- Choose a sunny location that is in full sun for the best results.
- When seedlings grow larger, remove the bottle cap and allow the plant to acclimate.
- Before planting in the garden, place the bottom portion outdoors for a few hours to eliminate shock. Bring them back inside and increase the time outside until they are ready to be planted. This prevents shock and should only take a few days.
- Jiffy pots are meant to go straight into the ground; do not remove the plant from the pot.
Kid Friendly Tips
This DIY plastic bottle greenhouse is a wonderful hands-on project to do with kids. Once an adult has safely cut the plastic bottle and removed any sharp edges, children can fill the Jiffy pot with soil, plant the seed, mist it with water, and add their own label. Watching their seed sprout inside a tiny greenhouse turns the project into a fun science lesson about how plants grow. It’s a simple way to encourage patience, responsibility, and curiosity, all while creating something they’ll be proud to care for.
Have them create their own label and care for it until it is ready to go into the garden.
If the edges of the cut bottle remain sharp, cover them with masking tape pr dict tape to prevent cuts. Choose pretty decorative duct tape for a personal touch.
Creating your own plastic bottle greenhouse is a simple, fun, and eco-friendly way to start seeds indoors. Not only does it give your plants a healthy head start, but it’s also a perfect project to do with kids or as a weekend craft for yourself. With just a few supplies and a sunny windowsill, you can turn empty bottles into little green worlds that grow life and maybe even a love for gardening. Give it a try, and watch your tiny seedlings thrive!
This website contains affiliate links. As an Amazon affiliate, I earn a small commission from qualifying purchases (at no cost to you).