What you need to grow herbs in water
A simple way to grow herbs yourself is to root the herb cuttings in plain water using glass bottles.
What type of water?
Avoid using chlorinated tap water directly. Tap water that has been left to air overnight is fine, so is stored rainwater. Spring water or well water is the best because it has some amount of dissolved minerals that may be of use to plants.
What kind of container?
As for the container, jam jars or any other glass bottles will do.You can even use plastic bottles.
Roots generally like to grow away from light. Coloured bottles, especially amber coloured ones, are great.
You can also wrap a piece of paper around the bottle to keep the roots in the dark. This will even prevent algal growth on the container walls and on the root surface.
Narrow-mouthed containers have an advantage: they can support the cuttings and keep them nearly upright. However, the mouth of the container shouldn’t be too narrow or tight-fitting around the cutting.
The roots must breathe, and the mouth of the container should allow free movement of air.
What about the cuttings?
Soft cuttings are fairly quick to root in water.
The best part of growing herbs from cuttings is that you can use the ones you get from the supermarket. Just wash them in plain water and cut off the lower portion.
- If you have some herbs growing in the garden or the windowsill, snip off 6-inch sections from growing tips and put them in the water-filled containers.
- Remove lower leaves from cuttings and trim the lower tips close to the nodes from where the roots arise.
- When they are inserted into the bottles, there shouldn’t be any leaves touching the water. They can rot easily and spoil the water, as they do in flower vases.
- Change the water once a week without disturbing the cuttings.
- Once the roots start growing, usually between 2-6 weeks, water changes may not be necessary.
Woody cuttings like rosemary may take longer to root, so be patient.