Entretenir des begonias tubéreux selon Botanus

BOTANUS INC
PO Box 3184 Langley BC V3A 4R5
T: 1‐800‐672‐3413 • 604‐513‐0100 • F: 1‐800‐603‐3677 604‐513‐0192
www.botanus.com

Planting Tuberous Begonias


Tuberous Begonias take a while to show growth and in order to get a jump start on the flowering season we recommend that you start your tubers indoors and then transplant them to their containers once budding leaves form. To encourage earlier budding we would like to recommend you follow these steps:

The most important requirement for the medium used to start tubers into growth is excellent drainage ‐ we recommend a plain mix of 50/50 peat and coarse sand. Place the mix in containers or trays that are at least
2.5”/6 cm deep and place them directly on a heat source if available i.e. heating pad, top of fridge ‐ if a heat source is not available place the containers in a warm, well‐lit situation.

Push the tubers into the prepared mix, bud side up (the rounded side is the root side!). Tubers should have at least 2”/5 cm of space all around to allow for good root growth and should then be thinly covered with additional mix to encourage them to grow roots over their whole surface. Check the mixture for moisture ‐ it is most important to avoid over watering especially if bottom heat is lacking.

Once the top growth has reached at least 3”/7 cm the tubers can be transferred to their planting container – it is important that this container also provide good drainage. When transferring the root ball to the new container do not press the mix down too firmly as the young roots are very tender and again, over watering should be avoided at this stage while growth is slow. Once outdoors choose a shady spot protected from wind and when they are actively growing keep them evenly moist.

Standard, Upright Tuberous Begonias Grown in Pots
Shaping & Securing the Bud

If you’ve grown tuberous begonias in pots before and wondered why the results were not magnificent, it could be they need shaping and you can choose to do the following to increase the size and number of blooms. The shaping of a standard tuberous begonias should be thought about in the early stages of growth. At that time you might want to consider the number of new shoots that you will allow to reach maturity. Smaller, or first and second year tubers, can do better if only one stem is left to grow to maturity as more than one can result in weak stems and smaller flowers. On large tubers it’s recommended to allow two or three to grow on and flower.

When choosing which stems you will allow to grow to maturity you must be careful to choose the most vigorous growers and be mindful how the plant will shape up after the removal of any stems. You want to be sure any stems left will form a pleasing shape on which the flowers will be facing out. When you have chosen the stems you want to remain on the plant simply pinch off the weaker ones.

The next step to a beautiful flowering plant is to pinch off the buds of this standard begonia until
you have at least 8‐10 leaves, after that you leave the buds on to bloom later in the season. By
doing this you have ensured that the plant and its root system are large enough to provide
nutrition and support for those blooms. When the buds start to appear you can begin another
process, which will enable even better blooms. Each large bud on a standard begonia will have two
smaller buds on either side of it. The centre bud is the larger male flower and the other two are
usually smaller and are usually single females. The smaller females can be removed as soon as
possible to help increase the size of the male bloom.

Pendula Begonias in Pots
Improving the Display

Pendula begonias require a different approach for improving the bloom and the reason for the
difference is with pendulant begonias you want lots of blooms hanging down as opposed to the
bigger blooms of the upright varieties. So to achieve the best show for the pendula begonias you
want to leave on all the growing shoots of the hanging plant. When it is growing well and they are
between 6‐8” / 15‐20 cm long, all flower buds and the growing tip of each stem should be pinched
off, as well as any side shoots. What this does is forces the shoots to branch out and eventually
produce more blooms. With the pendulas you want to leave on the all the buds, male and female,
remember it’s mass effect you’re going for. Doing this does delay the blooms for a while so if you
got a late start planting this should not be attempted or your blooms will come when the season is
ending. The procedure for winter storage is the same as with the potted upright begonias.

Over‐Wintering Your Begonias


Once the blooms have finished and the plant is spent you should allow the soil in the pot to dry out
completely. When it’s completely dried out you can take the tuber out and knock the soil mix away
from the tuber and roots, be careful not to damage the tuber itself. Using a soft brush at this point
is helpful to gently remove all remaining dirt and loose bits. Now is the time to cut away any rot
that you can see on the tuber and then dust it with an anti‐fungal powder. They now should be left
in the sun, if possible, to dry out and then it’s into storage for the winter. The best solution for
storage is placing the tubers in shallow trays of a vermiculite and peat moss mix that is completely
dry. They must be stored in a place where there is plenty of air circulation and it’s safe from frost or
freezing. Be sure to check on them a couple of times per month during the winter, to be sure they
are faring well, no mold or bugs of any kind.