If using a smaller, thinner vessel like a test tube or beaker, plan on one cutting per container. There's a common theory that glass colored blue or green works best for propagation, but this is a myth. Clear glass vessels are actually better for supporting root growth—and they look pretty, too.
Roots themselves are also light-sensitive, so despite the fact that they will absolutely grow in a clear container in sunlight, you will find more success and faster propagation as well as avoiding algae growth in a dark glass or opaque container.
Fill a tall, skinny glass with water and place your cutting into the water. We recommend using clear glass for these plant propagation techniques because it will allow you to track root growth more easily, but any tall, skinny, watertight container will work in a pinch.
Cuttings can take in water from the air through pores in the leaves called stomata. To trap humidity, plant your cuttings in wet soil, use a spray bottle to mist the leaves, and cover them with clear plastic as described before. Then, place your cuttings in a warm spot.
Quick tip: While you can theoretically use almost any small container to water propagate, clear glass is preferable because it allows you to easily monitor the root growth and water level/quality. Plus, it's fun to easily see those roots developing!
Some plants will root in water, but cuttings will develop a better root system when rooted in a soil-less potting mix. Sand or perlite can also be used, especially for cuttings that need good drainage and may rot if kept too wet.
With the exception of succulents, most cuttings need high humidity in order to grow properly. Until cuttings develop roots, they are very susceptible to drying out. If you don't have a bright area with high humidity, you can create a humid environment around the cutting by placing a clear plastic bag over it.
Cover the Pot With Plastic
Place the container with the cutting into a plastic bag. The bag will keep the humidity high and hold in heat. Do not seal the bag completely because some airflow is necessary to prevent fungal rot.
The cutting should be placed in a suitable medium and encouraged to grow as an independent plant) are a part of the original stock plant (the plant which is used to obtain propagating material, plant cuttings are taken from the stock plant) and they share the same balance of light, air, water, and nutrients as the ...
Light provides the energy for callus formation and the subsequent generation of adventitious roots. At the same time, light increases plant temperature and accelerates the drying of leaves, which can quickly dehydrate cuttings. (Under LEDs, this would be less of an issue.)
Adding supplemental lighting to cutting (clone) production can greatly increase the chances of a successful crop, along with faster root emergence and crop times. If the Daily Light Integral (DLI) is too low during propagation, leaves will be unable to get enough light for photosynthesis and rooting can be delayed.
Of course colored glass rooters are more attractive that plain old glass jars. And that's a perfectly valid reason to use them as part of one's home decor. But it's not science, nor is it necessarily the best way to encourage rooting.
Cuttings need water for hydration, but also enough oxygen for roots to respire and grow. Using a substrate with adequate air porosity, and using the 1 to 5 moisture scale can help to prevent overwatering that leads to slow rooting and increased risk of disease.
Clean, coarse construction-grade sand may be used for rooting cuttings. Avoid very fine sand because it has poor aeration, which hampers root formation. A mixture of half sand and half peat moss is a better rooting medium. Vermiculite, a lightweight expanded mica product, is suitable for rooting cuttings.
Using sickly plants or flowering shoots
Cuttings are very delicate and vulnerable so pests, disease, the wrong growing conditions, too much water or too little water can all cause them to fail.
The sooner you can get your cuttings into a more normal environment with air flow and no dome, the better off they'll be. After about a week, remove the dome and monitor your cuttings to see if they begin to wilt. If they do, they're not ready to go dome-less, so try again in 1-2 days.
Technically, you can transfer your cuttings to soil at any time. In fact, you can actually propagate directly into soil, however, it's much harder to do within your home. When you propagate in soil, you have to keep a good balance of soil moisture, air flow, and humidity.
Carefully remove excess leaves to reduce transpiration, so cuttings do not wilt. However, some foliage should be retained to allow photosynthesis to occur. Keep cuttings moist, cool and shaded (collecting in a damp plastic bag is a good idea) until you are ready to put them in a propagation medium.
Should we allow the cuts to dry out a little before sticking them in medium? No - while herbaceous cuttings are less likely to rot, they also root faster than woody plants because they contain less lignin in their stems. Don't give them time to dry out.
Warm growing medium temperatures accelerate cell division which leads to faster callusing, root initial development and subsequent root growth. It also speeds up the dry-down rate of the growing medium, which also helps encourage better rooting. The best way to warm the growing medium is through bottom heat.
The technique is the same for almost all cuttings – cut a length of stem without flowers about the length of a pencil. Trim it neatly just below a node (the point where the leaves branch from the stem), and cut off the lower leaves to give you a bare stem. Put it down the side of a pot into gritty, free-draining soil.