Turn your plastic bottles into miniature greenhouses.
The cloche or bell jar is a miniature greenhouse contraption designed to protect seedlings from cold, bleak, or windy weather in order to hasten their maturity.
Traditionally, it is a dome made of glass that can be completely sealed (such as the bell jar) or have a small opening at the top. The bell jar creates humidity and warmth but must be adjusted as the heat and light intensifies. The open cloche allows heat to escape on its own and allows water to trickle down into the soil during a heavy rain instead of drowning the seedling.
Cloches can be expensive. Homemade versions can be made using turned over mason jars or other thick-walled glass items. These are pretty to look at in the garden, but they must be watched intently to avoid scorching seedlings or promoting fungal diseases.
If you’re willing to sacrifice a little beauty for a fully functioning device that is not only as cheap as it gets (as in free), but will go the distance, then the plastic bottle cloche is the way to go. I can’t praise this contraption enough. It has prevented critters such as raccoons and squirrels from trampling or eating my seedlings, and provided warmth and humidity during an unseasonal frost spell. It prevents potted plants from becoming enveloped in mudcakes formed during torrential spring rains, and forms a barrier against insects and slugs.
To top it all off, my seedlings are growing faster, stronger and healthier than ever before.
There are two devices that can be made from a bottle. The first is a full cloche that can be used as described above. The second is more of a ring that forms a barrier around the plant but leaves it open to attack from the top. It creates humidity around small seedlings and to the stem and base of older seedlings. This is especially good for protecting older tomato plants from slug attacks and can be left on all year long.
To make a full cloche:
- Remove the cap and all labels from a plastic pop or water bottle.
- Use a serrated knife to cut about an inch off the bottom. Try to get as close to the bottom as possible to maximize your cloche height. Alternately you can cut it down more if you prefer a shorter cloche. Just be sure to add an extra inch for support underneath the soil.
- Place the cloche over your seedling and bury it about an inch into the soil for support.
- Once the plant becomes too large for the cloche simply cut it down into a ring and leave it around the plant indefinitely, or remove it and throw it into your recycling bin.
To make a protective ring:
- Remove all labels from a plastic pop or water bottle.
- Use a serrated knife to cut about an inch off the bottom. Try to get as close to the bottom as possible to maximize your ring height.
- Cut the top off where the bottle begins to form a dome. You should be left with a cylinder of plastic. This can be cut in half to create two rings or cut down to reduce the height. Just be sure to leave an extra inch because this will be buried in the soil.
- Place the ring around your plant and bury it into the soil for support (and to prevent critters from going underneath).
- The ring can be left around the plant indefinitely to provide protection all season long.