How Much Water Do Begonias Need? A Guide to Proper Watering

With their colorful blooms and attractive foliage, begonias are a popular choice for gardens, containers, and indoors. But like any plant, they need proper care to thrive. When it comes to begonias, getting the watering right is key. Understand their requirements and you’ll be rewarded with beautiful, long-lasting plants.

The Importance of Consistent Soil Moisture for Begonias

Begonias demand consistently moist, but not soggy, soil. Erratic watering leads to a number of problems:

• Allowing pots to dry out completely stresses begonias, resulting in dropped buds and yellowing leaves

• Overwatering can lead to root rot and stem or crown rot diseases

• Wet foliage left overnight encourages powdery mildew and other fungal diseases.

The sweet spot is keeping the soil moderately and regularly moist. This provides begonias the water they require without going to extremes.

How Often to Water Potted Begonias

For container begonias, check soil moisture daily and water when the surface just begins to dry out. During peak summer heat, this may mean watering every day or every other day. In cooler weather, you might water every 3-4 days.

Poke your finger into the soil to gauge moisture levels. If the top inch is dry, it’s time to water. Apply enough water until it drains freely from the pot’s bottom drainage holes.

Allow pots to drain fully before returning to saucers to avoid standing water. Empty out any accumulated water in saucer after 30 minutes

Watering Frequency Guidelines for Begonias

As a general rule, follow these guidelines for how often to water your begonias:

• Houseplant begonias – Every 5-7 days in winter; up to every 2 days in summer

• Outdoor container begonias – Every 2-4 days; daily in peak heat

• Bedding begonias – 2-3 times per week if rainfall is lacking

• Tuberous begonias – Keep soil consistently moist but not soggy

• Rhizomatous begonias – Allow to slightly dry between waterings

Adjust frequency based on your climate, time of year, and growth rate. Watch plants for wilt signals it’s time to water.

How to Tell When Your Begonia Needs Watering

The plant itself will display signals that it’s thirsty and needs a drink. Watch for these signs with your begonias:

• Leaves appear limp, droopy or curled

• Flower buds shrivel and fall off without opening

• Leaves turn yellow or develop dry, scorched edges

• Growth slows down or stops

• Soil pulls away from sides of pot or feels dry when pressed

Don’t wait until severe wilting occurs to water, as it stresses the plant. Water at first indications of dryness.

Wetting Begonia Leaves When Watering

Ideally, water begonias at soil level and avoid splashing or spraying the foliage. Wet leaves left overnight raises humidity and can promote powdery mildew, botrytis, and other diseases. However, this is difficult to entirely prevent.

If you do happen to get the leaves wet when watering, try these tips:

• Water early in the day so foliage has time to dry off

• Use soaker hoses or drip irrigation to target soil

• Water from below using pots set in trays filled with water

• Wipe excess moisture off leaves or increase air circulation

Humidity Needs for Begonias

Begonias naturally grow in tropical and subtropical forests where humidity is high. Replicating these steamy conditions helps them thrive.

• Stand pots on pebble trays to increase local humidity

• Group begonias together so they benefit from each other’s transpiration

• Use a humidifier in dry indoor air

• Avoid drafts from heaters, AC vents, or fans

Boosting humidity reduces leaf scorching and drooping in arid environments.

Water Requirements for Different Begonia Types

While basic watering guidelines apply to most begonias, some species have slightly varying needs.

Tuberous begonias – Require consistently moist soil, especially when first planted and during flowering. Allow to dry slightly between waterings once established.

Rex begonias – Water when soil feels almost dry but don’t let potting mix totally dry out. Lower leaves will shrivel if too dry.

Trailing begonias – Check soil daily and water when surface just dries but before plants wilt. Don’t leave sitting in water.

Hardy begonias – Can handle some dryness but avoid drought. Supplemental watering needed during dry spells.

Rhizomatous begonias – Allow soil to partially dry out between thorough waterings. Don’t keep overly wet.

Bedding or garden begonias – Need consistently moist soil. Water 2-3 times per week if rain is lacking.

Providing Proper Drainage for Begonias

While begonias like steady moisture, they detest soggy soil. Ensuring proper drainage prevents wet feet and potential root rot. Use these tips:

• Select pots with bottom drainage holes to allow excess water to exit

• Add perlite, pebbles or bark to potting mix to improve drainage

• Position outdoor pots and beds to avoid standing water

• Water potted begonias from below to avoid waterlogged soil

• Check for compacted or dense soil impeding drainage

• Consider terra cotta pots which naturally dry out faster

Begonia Watering Tips and Mistakes to Avoid

Follow these key tips to keep your begonias happy when watering:

• Check soil moisture frequently to gauge water needs

• Apply moderate amounts of water when surface just dries out

• Allow pots to drain fully after watering to avoid soggy soil

• Empty water from saucers so pots aren’t left sitting wet

• Increase humidity for begonias in dry air environments

• Wet foliage early in day to allow time to dry before night

And be sure to avoid these common watering mistakes:

• Allowing potting mix to completely dry out between waterings

• Overwatering leading to saturated, soggy soil

• Splashing a lot of water on leaves without wiping them dry

• Letting pots sit in saucers of water without drainage

• Failing to increase watering frequency during hot, dry weather

• Watering late in the day so leaves stay damp overnight

Achieving the Ideal Moisture Level for Healthy Begonias

Begonias thrive best when the soil is moderately and consistently moist. Take cues from the plant, climate, and growing conditions to determine optimal watering frequency and volume. A little trial and error will help you dial in the ideal moisture levels. Proper watering technique along with good drainage provides the foundation for growing robust and floriferous begonias.