Flower size is not affected by tuber size, but by the number of stems on each tuber. To accustom the plants to outdoor conditions, begin hardening them off about two weeks before the last frost date. Roots will develop from the bottom, sides and top of the tuber, and stems will sprout from the top. Some varieties, such as those used in hanging baskets, are grown for quantity of flowers, not for large blooms. It’s easy to propagate begonias with simple cuttings and every experienced gardener tweaks the basic methods to suit their own talents. Tamp down the medium to hold the cutting upright. All rights reserved. Pull off stems and any roots or soil, but don't wash the tubers. Rooting begonias this way gives me more control over the moisture content of the container. Set the Forsythe pot in a warm place with bright indirect light. If you are planting your begonias in a garden bed, make sure to choose a spot with the right amount of light and well-drained soil. Although some growers divide begonia tubers, they must make the divisions when the plant is actively growing, and the tuber pieces often become diseased and rotten. A favorite of mine is to line your pot with a plastic bread bag with a few holes poked in the bottom for drainage. begonia cuttings directly into a growing medium. Tuberous begonias are popular for their beautiful flowers that come in a variety of colors and forms. The clay pot is a water reservoir, so you will not need to water the cuttings as long as you keep it filled. Tuberous begonias will enter a dormant period no matter how they are grown, whether in a greenhouse or outdoors, so they are not suitable as year-round houseplants. Rooting Mediums and containers Tuberous begonias are sensitive to cold and should not be put outdoors until the nights are above 50°F. Propagation: Propagation is an important part of the seasonal cycle. After about one month, the stems will be 1 inch tall. There are two basic ways to propagate begonias through begonia cuttings: stem and leaf. Tuberous begonias bloom throughout the summer, thriving in shady spots where few other plants with long bloom periods and showy flowers can grow. Nearly all begonias can be started from stem or tip cuttings. Before you take the cuttings, prepare what is called a forsythe pot in which to root them. Many gardeners prefer to create a mini hothouse when they propagate begonias to keep the soil evenly moist. Birds do it, bees do it, and even begonias do it—they make babies. Growing Begonia Rhizomes – What Is A Rhizomatous Begonia, Classifying Begonias - Using Begonia Leaves To Help Identify The Begonia Class, Do I Need To Prune A Begonia – Learn How To Prune Begonias, Prickly Kale Leaves – Does Kale Have Thorns, Corn Husk Wreath Ideas: How To Make A Corn Husk Wreath, DIY Air Plant Wreaths: Wreath Making With Air Plants, Prepare New Rose Beds – Learn More About Starting Your Own Rose Garden, Growing Geraniums: Tips For The Care Of Geraniums, Thanksgiving Tradition: Turning Homegrown Pumpkins Into Pie, Growing Thanksgiving Dinner – Must Have Turkey Side Dishes, Interesting Uses For Pecans: What To Do With Pecans, The Bountiful Garden: Bringing The Garden To Thanksgiving. Cut the stems to be rooted and insert them into the moist vermiculite. Press seeds onto the surface of the medium and cover them lightly with milled sphagnum. Although tuberous begonias must be grown in well-drained soil, they are not drought tolerant, so it's important to water them when it hasn’t rained. Once you have plants, choose a site for tuberous begonias that is somewhat protected from wind, where the soil is well-drained, and plants will be shaded during most of the day. Plant the tubers 1” deep in moist growing mix and water sparingly. Fill with soil, plant, lift the sides of the bag up and secure with a plastic tie. If they're growing in the shade of trees or in containers under a roof, you must pay even more attention to keeping the soil properly moist. Why not try them both and see which one works best for you? Some gardeners may choose to remove any flower buds that form in September to encourage dormancy and the storing of energy in tuber. In late winter or early spring, purchase tubers or start those you have stored. Once the weather has settled, the soil is warm, and all danger of frost is past (usually by late May or early June in Minnesota), transplant them to hanging baskets on the porch or out in the garden, or move containers to their permanent place on the deck or patio. Thin the seedlings to 2 inches apart. Place the flats where the temperature is around 70F, and they will receive indirect light. (Tissue culture was tried for several years but was never really successful). Early morning and late afternoon sun will not harm them, but they need good indirect or dappled light at other times. Tuberous begonia species are native to tropical South America and southern Africa. For me, a more sure fire way of propagating begonias is to plant those four inch (10 cm.) Otherwise, fill the flat with fresh peat moss or vermiculite. Place the tubers in a perforated plastic bag filled with peat moss or vermiculite. Tuberous begonia flowers come in many different colors and shapes. They are often used as container plants on patios and porches, in hanging baskets, and as bedding plants. For the larger leaved plants, begonia propagation can begin with a single leaf. Starting tuberous begonias from seed is certainly an option, but will take time and expertise to bring the seedlings to flowering plant size. Tuberous begonias do not not grow true from seed, so the only way to increase identical stock is by taking cuttings. Gradually reduce watering and stop fertilizing at the end of August. If the stored tubers show no signs of disease, you can use the same medium in which they were stored. The stems sometimes rot, especially if the sunlight is too direct, leaving a mushy goo in the glass; and tap water contains traces of chlorine, which can poison the young shoots. Rexes, rhizomatous, tuberous, and a few other types can be started from leaf cuttings or portions of leaves. Left in the ground during a Minnesota winter, they would be killed. Try propagating your begonias to share or save. Tubers started in February should begin to bloom in June; those started in March or early April should bloom in July. Regents of the University of Minnesota. Follow the directions above only bury the petiole (leaf stem), not the leaf. Moisten the vermiculite, then fill the clay pot with water. Rooting begonias aren’t fussy about the medium they’re grown in as long as it’s light and retains moisture. Small tubers will produce small plants; large tubers, large plants. The University of Minnesota is an equal opportunity educator and employer. Leave the plastic or glass on for one or two days after germination, then remove it. Why not use your garden plants to start whole new plants for your winter window sills by propagating begonias? Harden the plants off, then plant them in hanging baskets, in larger containers, or directly in your garden. Find more gardening information on Gardening Know How: Keep up to date with all that's happening in and around the garden. Place the tubers an inch (2.5 cm.) Move the plants outdoors on a warm day to a shaded, protected place. If you are growing them in pots, use a high quality, humus-rich growing mix. Some gardeners cut a small piece of tuber with each shoot to increase the chances of the stem rooting, but the wound on the tuber may allow disease-causing organisms to attack the tuber. For earlier blooms, start your begonias indoors, eight weeks before the last frost date. With a sharp knife, cut a mature leaf from the plant where the leaf meets the stem. Fill containers with fine-textured potting mix and moisten it. Lift the tuberous begonia from the soil, and shake off any loose soil that is attached to the tubers. Dig begonia tubers when the foliage starts to yellow, or after the first killing frost. When they become crowded, transplant them to larger pots, using a porous, well-drained potting mix. Sign up to get all the latest gardening tips! Cut just below a node. Bring them back in before temperatures cool off at night. Thinning stems. The three most popular types of garden begonias are the tuberous types, which are large leafed and sold either growing in pots or as brown tubers for do-it-yourself planting; the rhizomatous, commonly called Rex begonias; and the old fashioned wax, which are known as fibrous rooted.