Begonias, known to us as the stars of the shade garden, delight with large, spectacularly colored blooms that last through the summer season. These beauties thrive in containers or in the garden, preferring shade and rich soil.
Begonias are not the easiest tubers to plant – they take longer to bloom than other summer bulbs and should be started indoors in the late winter. But they are well worth the extra effort, as their huge, colorful blooms steal the show in almost any summer garden.
When To Plant
We recommend starting the tubers indoors in the late winter, around February or March. However, the tubers can be planted from February to June. In areas with hot summer temperatures, it’s best to have Begonias established earlier in the season. In colder zones, tuberous Begonias are tender and cannot be placed outdoors during frost. Come spring, once the ground warms and the chance of frost is over, bring your Begonias outdoors and either keep them in containers or transplant into the garden.
Where to Plant
Outdoors: Begonias prefer shade, rich soil and require some regular care, so try to plant them in an area that is easily accessible. We recommend watering every few days, or when the soil has dried out. Fertilize every other week with an organic 20-20-20 fertilizer.
Indoors: If you’re starting tubers inside, place planted Begonias in a warm location with indirect sunlight, preferably an eastern, western, or southern-facing window. If you don’t have an indoor window space, we recommend purchasing a heat lamp to allow some light for growth (heat lamps also come in handy for starting seeds).
Step 1: Prepare your garden plot or container. If planting in a garden, dig a hole a few inches deep to cover the tuber. If planting in a pot, find a pot that is twice the size of the tuber. Fill the pot 3/4 full with potting soil. Soil mixes with peat moss are the best choice, because they retain moisture and create slightly acidic conditions. We recommend using a 2/3 peat moss and 1/3 potting mixture.
Step 2: One side of the tuber has a hollow dip and the other is round; the hollow dip is the top and sometimes they will already be sprouting buds. If the buds are coming up, be very careful placing the tubers in the pot as the new growth is fragile.
Step 3: Cover tuber with soil and water. Keep your container or garden bed moist, but not too wet. Expect growth in 3-4 weeks after planting. If growing conditions aren’t ideal, Begonias can take longer to grow. That’s why planting in containers is often a great choice for Begonias; if they aren’t thriving, you can always try moving them to a different location in your garden.
Step 4: If you’ve planted indoors, after Begonias have sprouted and are a couple of inches tall, you can transplant outdoors. If you live in a older climate and the chance for frost has passed, you can place the Begonia outside.
In fall, after leaves turn yellow or temperatures reach below 40 degrees at night, bring your Begonias inside and enjoy as a houseplant or save for next spring. In colder zones, lift tubers and store in a cool, dry non-freezing place until spring. Allow tubers to dry out for 5-7 days before storing to reduce mold and rot. It’s best to place in a cardboard box full of peat moss or a paper bag for storage.