Recycle a plastic bottle into a very simple mini-greenhouse for seedling growth (Willem Van Cotthem / Tine DAU)

It is extremely easy to transform (recycle) a plastic bottle into a mini-greenhouse.

Here are Tine DAU’s photos showing how simple and cheap that is:

Plastic bottles transformed into a mini-greenhouse in which a bell pepper seedling is growing (Photo Tine DAU)

On the foreground, a seedling is growing in a small bottle of which the bottleneck has been cut off.  Two opposite drainage holes at 2-3 cm above the bottom of that bottle avoid that too much water could stand in the base.  It is partly filled with an organic potting mix (local dirt with some manure).

The taller bottles (1,5 liter) in the background have been cut transversely (cross) for almost 95 % at 10-12 cm (4-5 inches) above the bottom, leaving the upper part of the bottle attached at the bottom part over a length of 2-3 cm.  Thus, the upper part can be bent over to open the bottle and fill the bottom part with potting mix, in which the seedling can be planted.  Do not forget to perforate the bottom part with two opposite holes for drainage.

Finally, the upper part is put back in its original position (as if the bottle is still intact).  Thus, the seedling is growing inside the bottle, acting as a mini-greenhouse.

Left : two mini-greenhouses – Right : upper part taken off (Photo Tine DAU)

One can also control the humidity inside the bottle by :

(1) leaving the cap (lid) on top, which creates condensation of the evaporated or transpired water on the bottle wall;

(2) taking the cap off to let water escape through the bottleneck.

This can be interesting for growing seedlings in the drylands or in drought-affected regions.

Mini-greenhouse bottles with their cap on, keeping water inside, which condensates on the wall (Photo Tine DAU)

Grown to a maximum in the bottle mini-greenhouses, the seedlings can be transplanted into other containers (pots, buckets, sacks, bags, barrels, drums, …) or can be planted directly in the soil.

Bell pepper seedlings transplanted from their mini-greenhouse into pots (Photo Tine DAU)
Young bell pepper plant already flowering in a tiny little bottle (Photo Tine DAU)


Saving water (almost no water loss)

Higher temperature inside the bottle

Sufficient light inside the bottle

Less variation in temperature around the seedling

Protection against insects

Better and faster seedling growth

Published by

Willem Van Cotthem

Honorary Professor of Botany, University of Ghent (Belgium). Scientific Consultant for Desertification and Sustainable Development.