Deciding how often to water outdoor potted plants can seem tricky. Proper watering is essential for healthy plant growth, but overwatering can cause just as many problems as underwatering. When it comes to outdoor container gardening, getting the watering schedule right makes all the difference.
With some key tips in mind, you can figure out the optimal watering frequency for your own outdoor potted plants. We’ll cover all the factors to consider and techniques to help keep your plants perfectly hydrated.
How Much to Water Outdoor Potted Plants
When watering outdoor container plants, the most important rule is to thoroughly soak the entire root ball each time. Light sprinklings of water lead to shallow roots and encourage fungal growth. Instead, you want to drench the soil until water drains freely from the bottom of the pot.
The amount needed to saturated the soil depends on:
- Container size – Larger pots need more water to moisten the entire soil mass.
- Soil composition – Fast-draining mixes require more water before it starts running out the drainage holes. Potting soil with lots of peat or moisture-retentive amendments needs less per application.
- Plant size and type – Small or newly transplanted plants use less water than established, mature ones. Some varieties also naturally prefer drier or wetter conditions.
Get to know how much water your individual outdoor containers need. Lift the pots to get a feel for their water weight when the soil is fully moist. Then allow to dry out before soaking thoroughly again. The containers should feel significantly lighter when it’s time to water again.
How Often to Water Outdoor Potted Plants
The ideal watering frequency varies by a few factors:
Weather and Temperature
Outdoor plants require more frequent watering during hot, dry weather. When temperatures rise and the sun beats down, container soils lose moisture much faster. Monitor pots closely during heat waves and periods of drought, and increase watering as needed.
Cooler temperatures and cloudy conditions slow down evaporation. When it’s rainy or cold outside, you can often go longer between thorough waterings. Don’t let pots sit waterlogged, though – even colder months require drainage.
Plant Type
Certain plants prefer drier or wetter soil conditions. Getting to know your plant’s preferences helps tailor its watering schedule.
Plants that enjoy drier soil include:
- Succulents like cacti and aloe
- Mediterranean herbs like rosemary, lavender, and thyme
- Fruiting plants like tomatoes and peppers
Moisture-loving varieties include:
- Tropicals like hibiscus, palms, and elephant ear
- Annual flowers like marigolds, zinnias, and petunias
- Leafy greens and herbs like basil, lettuce, and chard
Ask an expert for advice if you’re unsure of a specific plant’s ideal soil moisture range. Matching its preferences makes maintenance much simpler.
Potting Mix
Soil components affect drainage rates, which influences watering frequency.
- Potting mixes designed for cacti and succulents have excellent drainage. They require more frequent water yet allow the intervals between to be longer.
- Standard potting soil with lots of peat moss or coir holds more moisture. It can go slightly longer between deep waterings but doesn’t dry out as quickly.
- Using water-retentive gels or polymers in the soil mix can buffer plants against drying and extend the time between watering.
Experiment to find the best potting medium for your particular indoor plants. Well-draining soil is essential for healthy container growth.
Container Size
For any given plant, a larger container holds more soil and stores more moisture between waterings. A tiny 4-inch pot may need water every day. An oversized tub may go more than a week before drying out.
When repotting plants into a bigger container, start checking soil moisture more frequently. The extra space can retain more water and stay damp longer than the plant’s used to.
Monitor the plant and allow the soil to dry more before watering again. Gradually increase the intervals until you find the new happy spot.
Time of Year
During the active growing season (spring through summer), most plants need more frequent watering. Growth and transpiration happen quickly when conditions are warm, days are long, and the sun is direct.
In the winter months, scale back to allow soil to dry out more between deep waterings. Things slow down as daylight hours decrease and temperatures cool. But don’t leave plants to languish – occasional deep water is still vital, even in winter.
Signs It’s Time to Water Outdoor Potted Plants
Rather than sticking to a rigid timeline, let the plants themselves tell you when they need a drink. With close observation, you can spot multiple signals that show it’s time to irrigate.
Soil Moisture
The top few inches of soil may appear dry on the surface, but deeper layers still hold moisture. Insert your finger into the soil, at least 2-3 inches deep, to check for lingering dampness.
Dry, loose, crumbling soil is a sure sign it’s thirsty. Soil that feels evenly moist 1-2 inches down likely doesn’t need water yet.
Pot Weight
Lift your containers before and after watering to gauge their dry and saturated weights. Notice how light the dry pots feel, and how much heavier they are freshly watered. Then use the heft to help tell when they start drying out.
Leaves and Stems
Look for visual cues on the plants themselves:
- Wilting or drooping – The plant is stressed and needs a drink ASAP. Catch wilt early before permanent damage occurs.
- Leaves feeling dry or crispy – Especially on succulents, leaves lose turgor and start shriveling when the plant is underhydrated.
- Yellowing leaves – While not the only cause, inadequate moisture can lead to chlorosis and yellowed foliage.
- Crispy leaf edges – Brown crispy margins are a warning sign to increase water. Low humidity also accentuates this.
Growth Rate
When temperatures rise and plants are actively growing, their water needs increase. Faster transpiration and larger plant mass cause them to dry out quicker.
Keep a close eye on soil moisture when your plants are putting on new growth. Their increased thirst can sometimes sneak up between regular waterings.
Watering Tips for Outdoor Container Plants
Follow these tips and techniques to keep outdoor potted plants hydrated and healthy:
- Water early. Water first thing in the morning so the moisture has all day to soak into the root zone. Avoid afternoon/evening watering that can lead to diseases.
- Bottom-water when possible. Set pots in a tub of water and let the soil soak from below. This encourages roots to grow downwards.
- Add water retention gels. These polymers absorb and hold onto moisture in the soil mix. They increase the time between deep waterings.
- Choose containers with drainage. Holes allow excess water to drain out, preventing soggy soil. Elevate pots off saucers too.
- Consider self-watering pots. For low maintenance watering, self-watering containers with reservoirs slowly release moisture into the soil.
- Use drip irrigation. Drip systems deliver targeted water to each container. Set them to water on a schedule while you’re away.
- Water thoroughly. Instead of frequent shallow sprinkles, do occasional deep waterings that saturate the entire root ball.
Common Watering Mistakes
Some misguided practices spell trouble for outdoor container plants. Avoid these errors to keep your pots thriving:
- Watering on a rigid, fixed schedule rather than letting the plants tell you when they’re thirsty.
- Relying on a lawn sprinkler system to also sufficiently water containers.
- Assuming all plants have the same watering needs.
- Watering late in the evenings, leaving plants damp overnight.
- Letting the soil completely dry out and remain parched for too long.
- Not watering deeply enough to moisten the entire soil mass.
- Using a soil mix that doesn’t drain well and stays soggy after watering.
Get to know your plants, stick your finger in the soil, and adjust your watering habits according to each pot’s needs. Consistent soil moisture is vital for healthy container plants.
FAQs About Watering Outdoor Container Plants
How much water do outdoor potted plants need?
This varies based on container size, plant types, soil mix, and weather conditions. The key is to water thoroughly until liquid drains freely from the bottom of pots. Small containers may need daily irrigation. Larger tubs might go 4-5 days between waterings.
Should outdoor potted plants be watered every day?
Most plants don’t need daily water. The exceptions are very small pots, shallow bonsai dishes, or fast-growing annuals in hot, dry conditions. Judge by soil dryness rather than watering on a fixed schedule.
How often should large outdoor pots be watered?
In peak summer, large containers may need water every 3-4 days. When it’s cool or rainy, intervals can stretch to 5-7 days. Let the soil dry out almost completely between deep waterings.
Should outdoor container plants be watered from the top or bottom?
Bottom-watering helps moisture soak deep into the root zone rather than run off the sides of the pot. But occasional top water is beneficial too, to rinse off dust and prevent salt buildup. Alternate between both methods.
What time of day is best for watering outdoor potted plants?
Early morning, while it’s still cool, is ideal. It allows ample time for water to infiltrate without evaporating rapidly. Afternoon watering often loses too much to evaporation. Avoid evening watering that leaves them damp overnight.
Conclusion
Proper watering keeps container plants looking lush and vibrant. While there are general guidelines to follow, each plant has unique needs based on climate, container size, time of year, and other factors. Get to know your plants and let them tell you when they need a drink. With close observation and a little practice, you’ll have your outdoor potted plants perfectly hydrated.