Starting Tuberous Begonias Indoors

Late Winter Fun For Summer-Long Bloom!

From Your Friends At Schriemer's

Did you know that you can start your own begonias indoors? If you plant the tubers indoors in late February or March, you’ll be enjoying a full summer of spectacular flowers that will go right through until frost!

Here’s some hints and tips for giving your summer begonias a head start indoors;

1. Prepare to plant the bulbs indoors towards the end of March. Select large and firm tubers, looking for tiny sprouts starting on concave side of tuber; discard those that are soft or rotting.
2. Use 3” deep pots filled with good quality starting mix. The pots must have lots of drainage holes at bottom, as begonia bulbs are prone to rotting in standing water.
3. Plant the bulbs no more than 1/2” below soil level, tipping the concave depression slightly to the side when planting to facilitate drainage.
4. Water really well, then cover the pots with clear plastic wrap to retain moisture, removing the wrap as soon as sprouts are seen poking through soil.
5. Place in as much sunlight as possible in a warm location, and don’t water again until they sprout. The bulbs will usually sprout quickly but may take as long as a month depending on the variety.
6. Once sprouted, move the pots into light shade, not direct sunlight. Water only to keep soil moist, but make sure you don’t over-water. Fertilize every 2 weeks with an all-purpose fertilizer.
7. Start to harden off the plants when shoots are 6” tall by moving them outdoors on warm days and bringing them back in for the evenings.
8. Plant after all risk of late spring frost has passed, planting in partial to full shade, into extremely well-drained soil or into containers. Be careful to keep them out of strong winds, which can damage the foliage.