Root cuttings can be used to propagate a range of herbaceous perennials in late autumn or early winter when the plants are dormant.
Taking cuttings in autumn is also a good way of increase your stock of your favourite plants. At this time of year, you can take semi-ripe cuttings, from this year's growth. They are woody at the base and soft at the tip. In autumn, hormone levels are high, so plants should root and grow well.
September/October is the ideal time to take cuttings from your favourite strains of tender perennials to increase your stock for next spring or to make sure they live on if the parent plants do not survive the winter.
Hardwood cuttings provide an easy and reliable method of propagating a range of deciduous climbers, trees and shrubs, and as bonus, they are taken from mid-autumn until late winter when more time is usually available to the gardener.
Once the weather gets colder and you have experienced at least one good hard freeze, the deciduous plants should be dormant and will have dropped their leaves, and you can now propagate them. Just make cuttings about 4” long, dip them in a rooting compound and stick them in the bed of sand.
Hardwood cuttings are best taken in October and November once the new summer growth has gone woody.
Three of the best plants to propagate in fall are lavender, geraniums, and verbena. Since most lavender varieties hate cold weather (especially container varieties), they're a great plant to take cuttings from at the end of the growing season before a frost hits.
When to take cuttings. The best time to take softwood cuttings is from mid-spring to early summer. Hardwood cuttings are taken later in the year, from mid-autumn to mid-winter.
Most softwood cuttings are taken in spring and early summer, from the tender new growth of the season. If potted by mid-summer they will develop sufficient roots to survive the winter, otherwise pot up in the following spring.
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.
Being winter the time taken for the cuttings to strike is much longer. Generally it's going to take 2-4 months for roots to develop on a cutting taken during winter. This is due to temperatures and light conditions. Most plants understand what season it is based on the light.
Collect Gunnera and Juniper seeds. Divide Aconitum, Alchemilla mollis, Alliums, Aquilegia, Blueberry, Billberry, Campanula, Convallaria, Cranberry, Dicentra, Echinops, Hypericum, Lilies, Polygonatum and Sedum. Take Celastrus, Clerodendrum, Hedera and Laburnum cuttings.
“Grafting, budding, and plant propagation can be done on many types of plants during the winter, not just hardwoods.” High humidity and moisture are important during the post-cut and post-grafting periods.
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.
(Many plants will root successfully from cuttings without the use of rooting hormone, but using hormone can speed up the process, and it might be essential for some hard-to-propagate plants.) If you are using a powdered hormone, it helps to moisten the stem before rolling it in the powder.
Fuchsias, salvias and pelargoniums are easily propagated from cuttings taken in early autumn. They root quickly and are then easily kept indoors for the winter and early spring, ready for planting out next season. Penstemons, erysimums and hebes are also easily propagated from cuttings taken in autumn.
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.
Several cuttings may be placed together in one container. Be sure to add fresh water as needed until the cuttings are fully rooted. 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.
Taking cuttings is a great way to propagate new plants. You can take cuttings at any time of year in a variety of ways, but the easiest (and most successful) method is by taking cuttings of plants' stems in summer.
Numerous plant species are propagated by stem cuttings. Some can be taken at any time of the year, but stem cuttings of many woody plants must be taken in the fall or in the dormant season. Tip cuttings: Detach a 2 to 6-inch piece of stem, including the terminal bud. Make the cut just below a node.
A common rooting temperature target is 73 to 77° F. To accomplish this, propagators who grow on the floor use in-floor heating, which is usually installed when the greenhouse is built. This is usually an energy-efficient method to increase the root-zone temperature and second- arily, the air temperature.
Most cuttings taken in spring will be flowering in their first summer. Those taken in late summer will be overwintering under glass and be ready to harden off during May. One of the keys to overwintering rooted cuttings under glass is to keep them on the dry side in bright frost-free conditions of around 7°C (45°F).
80% of a plant's root growth occurs in the late summer and fall months. Root growth continues slowly through the late fall and winter, as long as the soil is not frozen. Better root growth increases the number of nutrients stored in the plant over the winter.
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.