Mini greenhouses provide the ideal growing environment for seedlings and small plants and can be used to rejuvenate houseplants that show signs of stress or decreased growth. Humidity levels inside the mini greenhouse increase, allowing plants to thrive without constant watering. Using two-liter soda bottles to create mini greenhouses for individual plants or seedlings is an inexpensive option that works well.
Remove the cap and soak a clear two-liter bottle in hot soapy water for 10 minutes.
Peel off the label. Scrub the glue residue with a kitchen scrubby to remove. Rinse with hot water and set the bottle upside down in a dish rack to dry.
Cut the bottom off the two-liter bottle at the point when the curved bottom ends and the sides straighten. Most bottles have a plastic ridge at this point that can be used as a guide for cutting. Puncture a hole with the point of a knife and cut around the bottle. Discard the bottom.
Trim around the cut edge with a pair of scissors to remove any rough or uneven edges. This edge sits in the soil. Minor rough edges pose no problems, but the cut edge should be even. Set the bottle on the table with the cut end down. If the bottle is lopsided, adjust your cuts to level it.
Place the bottle over a plant in a 5-inch pot and push the cut edge into the soil. Replace the cap and set the plant in indirect light. Plants in direct sunlight overheat quickly, causing damage to the plant.
Check the plant daily for any signs of mold or mildew. Soil should be moist, not soggy. If the soil is soggy, remove the cap to allow for evaporation. Replace when the soil has adequately dried.