An air bubble embolism, also commonly called an air bubble aneurism, is what happens when you’re cloning your plant and an air bubble enters the stem of your cutting. This is particularly apt to happen when you use older, duller scissors or clippers, so using a new, sharp razor blade to take your cuttings is always more preferable.
An air bubble in your stem is deadly to the would-be clone because it blocks the transfer of fluid and nutrients in the plant’s cardiovascular system. To avoid the risk of drawing an air bubble into your stem, here are some tips for taking and preparing your cuttings for cloning:
- Work quickly: prepare your cloning medium, rooting hormone and other materials ahead of time to ensure that you can process your cuttings in the shortest time possible from the time you take them off the mother plant to the time you put them into their rock wool, peat moss, plug tray, etc.
- Use sharpened tools, preferably new razor blades that are sterile, to ensure a smooth, clean cut; the goal is not to damage the inner bark, including the xylem and the cambium, as much as possible (dull tools cause more crushing of the stem, thus more damage).
- Do use rooting gel; the gel provides a liquid barrier on the stem / wound of your cutting, as well as containing hormones that encourage faster rooting.
- Make another cut: after you’ve harvested your cuttings, make another cut about ¼ – ½ of an inch higher than your original cut while holding the stem underwater. This will ensure that the stem will draw up water rather than a lethal air bubble.
Finally, if you’re taking a large number of cuttings all at once, or if you won’t be able to deal with preparing them and setting them up to root immediately, fill a bucket or vase with water and a light dose of nutrients; toss in an air stone or two and keep your cuttings in this water / nutrient blend until you have time to deal with them properly.