You can propagate houseplants at any time of year. This being said, the best time to do it is during their growing season – which is typically spring-summer. They will grow more slowly during the dormant months of autumn-winter.
When winter propagating, cuttings will need protection from the elements and some moisture. Protection may be in the form of a poly tunnel, kitchen windowsill, enclosed porch, or cold frame. Whatever you are using should be well lit, frost free, ventilated, and offer wind protection.
Herbaceous cuttings can be taken throughout the growing season (spring to late fall), while softwood cuttings should be taken in spring or early summer. Cuttings can be taken as long as the parent plant is healthy and in active growth.
Trailing philodendron can be propagated nearly any time of year, except for winter which is when the roots will grow exceptionally slow.
Cuttings from many annual plants will keep over winter, sprout roots, and be ready for planting in spring. You may place them in pots or cups without drainage filled with moist perlite or vermiculite. Locate them at first in bright light, away from the sun. Move later to an area where they receive morning sun.
Preparing cuttings
The plant material should be semi-mature, i.e. semi-hardwood. The best time, therefore, to take cuttings is late spring or early summer. Cuttings taken at other times will often root but may take much longer, although there are many exceptions.
Cuttings will root more quickly and reliably in warm rooting mix. Keep your cuttings between 65°F and 75°F, avoiding excessive heat. If your area is too cold, consider a heating mat or cable especially designed for this purpose.
You can propagate pothos in the winter, but the process may take a little longer.
Media is usually kept at 72-77° F while air temperature is maintained at 68-73° F. If bottom heat is not used, air temperature should be maintained between 77 and 80° F. Maintaining air temperatures lower than medium temperatures retards shoot growth while promoting root development. Excessive heat can damage cuttings.
Propagating Philodendron in Soil
You can also root philodendron directly in soil. Prepare a pot with holes in the bottom like you would for any new houseplant – this includes adding houseplant growing medium, water, and a few stones for added drainage.
Plant patents
Translation: you cannot divide that overgrown perennial, root cuttings, or layer branches if the plant is protected by a plant patent. Basically, the only legal way to reproduce a plant with this type of patent is by seed.
Some plants like papaya, marigold, chilli, capsicum, tomato, etc., cannot be propagated by asexual method. It is the only means of creating genetic diversity of plants. New varieties and cultivars of ornamental and vegetable crops can be developed only by this method.
As for timing, divide plants about four to six weeks before the ground freezes. Divide fall-blooming perennials in early to mid-spring. Plants in this category will have stored up energy in their roots over winter, which will facilitate their recovery from being divided.
All plants require light for photosynthesis, the process within a plant that converts light, oxygen and water into carbohydrates (energy). Plants require this energy in order to grow, bloom and produce seed. Without adequate light, carbohydrates cannot be manufactured, the energy reserves are depleted and plants die.
Fall Plants to Propagate
Cut a stem that has three to six nodes with sterilized pruning shears. Pinch off any blooms and leaves on the bottom third of the stem. Dip the freshly cut ends in rooting hormone and pot the cutting in small pots filled with sterile soilless mix that has been pre-moistened with water.
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.
Tend the Cuttings
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.
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.
The best time to propagate pothos is in the spring or summer months since this is the plants active growing period. Avoid propagating these plants during the fall and winter as its less likely to be successful. It will also be harder for the mother plant to recover from having stem cuttings taken during these months.
It is even easier to propagate pothos by cuttings. The best time to do this is in the spring, when the days are longer and warmer as the growing conditions are ideal. But you can take cuttings at any time of the year. Choose a shoot that has already grown aerial roots and cut it with a sharp knife.
The problem is if the cutting is too long the plant is more likely to wilt and stress. If the cutting is wilting it's far more likely to fail and not generate roots. Smaller cuttings will lead to better success rates and overall better outcomes for you and your cuttings.
The basic principle behind applying mist to vegetative cuttings is simple. Without roots, cuttings cannot adequately replace the water lost to the environment due to evaporation and transpiration mainly. To aid them along the beginning of their life journey we must replace this water loss with water applications.
It will slow transpiration while the necessary components are used at the root sites to build a new root structure. Keep the atmosphere around the cutting warm (not hot), keep the humidity relatively high (>90%), and keep the root zone temperature warm (at about 25°C).