Don't get the leaves wet!
Make sure no leaves are touching the water. If the plant has a crown – where leaves emerge from a central point – keep this above the waterline too. As a general rule of thumb, only stems should be submerged in the water as leaves and other parts are more susceptible to rotting.
Cut off any diseased roots using a sterile cutting tool like a knife or scissors. You want to make sure that you're cutting off the roots that are black and mushy. After you've cut off any dead roots, we recommend soaking them in an 80:20 solution of water to hydrogen peroxide.
Cuttings may be soaked in cool/cold water from 24-48 hours directly before planting to improve survivability. On site, the cuttings should be stored away from direct sunlight, heeled into moist soil, or stored in water until planting. Do not have cuttings in water for more than 4 days.
If this is not possible, stand the cut end in water or place the cutting in a plastic bag with a damp paper towel and store out of direct sun. If the plant is frost-tolerant, store the bagged cutting in the refrigerator. 2. For a stem cutting, remove some of the leaves.
It is best to harvest cuttings in early spring and plant immediately but if this is not possible, cuttings can be stored safely for about 4 months. Store cuttings in a cool, dark, and moist place. Do NOT store in a wet area as this will promote root growth and weaken the cutting.
Check for rooting
Rooting will generally occur in 3-4 weeks but some plants will take longer. When the roots are 1-2 inches long or longer the cutting is ready to be potted up.
Keep your cutting humid by loosely wrapping it in clear plastic. You can also create a makeshift greenhouse by placing the entire pot in a clear plastic bag. Place your planted cutting in bright light but avoid direct sunlight which can be too powerful.
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.
In general, Pilarchik notes, most cuttings should be about four inches long; two inches of the stem should be submerged in the water. Keep your cuttings indoors while they establish, as "the regulated temperature of a home will prevent stress and allow them to focus on rooting," adds Pilarchik.
Another product that'll help prevent the spread of root rot is non-flavoured cinnamon. After having removed the dead roots, sprinkle a thin layer onto the healthy tissue before placing into a bed of new compost.
Hydrogen peroxide can help to control fungal growth and fungal infection, such as root rot, by preventing the growth of fungi. It can also help kill fungus and bacteria on plant roots.
Control is difficult because once symptoms are observed, damage to the stem or roots is usually severe. For small flower beds and potted plants, use a soil drench of a recommended fungicide. A fungicide could also be mixed with soil prior to planting as suggested by the manufacturer. Allow excessively wet soils to dry.
Lack of oxygen
Plants absorb oxygen as well as other nutrients through their roots. As your plant sits in water, it releases carbon dioxide and absorbs all of the oxygen. If you don't change the water, it can run out of oxygen. This is the #1 cause of water propagation stem rot & root rot.
Once root rot is identified, you must determine if the plant can be saved. If the entire root system has already become mushy, it is too late to save the plant. However, if some healthy, white, firm roots exist, try to bring the plant back to good health by replanting in fresh soil with good drainage.
In soggy soil, drowning roots shut down and rot, and new roots can't form. Without healthy roots to absorb and transport water, plant tips turn brown from thirst.
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.
Give cuttings bright light but not sun. Keep soil moist but not wet. The cuttings should root within three weeks. Admit air gradually to wean the cuttings from their humid environment, then pot singly before outdoor planting.
Most plants will not root well in full sun, so place the cuttings in a location where they will receive a 50/50 ratio of shade to dappled sunlight. For most plants, cuttings thrive on warmth and humidity, and the growing medium should be kept evenly moist but not drenched while roots develop.
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.
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 cuttings in transit, you don't need to worry about it until after a week. It'll most likely be ok, if not totally fine. As for forgotten cuttings, you've probably got a good few days, depending on where it is.
Ensure Proper Moisture
Moisture and humidity are key in cloning, but wet is not good. Wet media lowers the oxygen levels in the media, which usually leads to rotting stems. Two of the most common medias used in cloning are rockwool and starter plugs.