Watering outdoor potted plants in summer can seem like a daily chore, but getting the watering schedule right is key to keeping plants happy and healthy. Here are some tips on how often to water outdoor potted plants when the weather is hot.
Factors That Affect Watering Frequency
How often you need to water depends on several factors:
Type of Plant
- Succulents and cacti need less frequent watering than annuals, perennials, and vegetables. Know the needs of each plant.
- Native and drought-tolerant plants adapted to your climate need less water. Tropical plants need more.
Pot Size
- Plants in smaller pots need watering more often than those in larger containers. Roots are more confined.
Type of Pot
- Unglazed terra-cotta pots lose moisture more quickly than plastic and glazed ceramic pots.
- Self-watering pots with reservoirs can go longer between waterings.
Weather Conditions
- Hot, dry, and windy conditions cause faster moisture loss so plants need more frequent watering.
- Shady spots and cloudy cool days allow going longer between waterings.
- Pay attention to local weather forecasts and adjust as needed.
Soil Type
- Sandy and fast-draining soils require more frequent watering than moisture-retentive loamy and clay soils.
- Add water-retaining amendments like peat moss if needed.
How to Tell When Outdoor Potted Plants Need Water
It’s important to check soil moisture rather than sticking to a rigid schedule. Here are some ways to know when to water:
- Stick your finger in the soil. If the top 1-2 inches are dry, it’s time to water.
- Lift the pot to check its weight. Light means dry, heavy means still moist.
- Observe the plant. Wilting or drooping leaves often indicate under-watering.
- Use a moisture probe for an exact reading of soil moisture levels.
Recommended Watering Frequency for Outdoor Potted Plants
As a general guideline for summer watering:
Annuals
- Annual flowers and vegetables: Water daily, even twice a day in very hot weather.
- Self-watering pots: Can go 2-3 days between refilling the reservoir.
Perennials and Herbs
- Drought-tolerant perennials like lavender: Water every 2-3 days.
- Kitchen herbs: Water daily or every other day.
- Self-watering pots: Check and refill reservoir every 3-4 days.
Succulents and Cacti
- Wait until top inch of soil is completely dry before watering. Can go 4-7 days between thorough waterings.
Shrubs and Small Trees
- Water established plants every 2-4 days depending on size.
- Newly planted specimens may need daily watering if no rain.
Watering Tips
- Water early in the day to reduce evaporation loss.
- Avoid overhead watering. Drip irrigation and soaker hoses work best.
- Water until it runs out the drainage holes at the bottom of the pot.
- Add mulch like bark chips to help retain soil moisture.
- Group plants with similar watering needs together on the same watering schedule.
Adjusting the Watering Schedule
- Check pots daily when temps exceed 85°F and increase frequency if needed.
- Reduce watering frequency in cool or rainy stretches.
- Newly repotted and transplanted plants need more frequent watering initially.
- Reduce watering for many plants in September as days cool.
Answers to Frequently Asked Questions
How often should I water potted plants in full sun?
Potted plants in full sun likely need water at least once per day during hot summer weather, sometimes twice a day if temps are very high. Check soil daily and water when the top inch is dry.
Should potted plants be watered every day?
Many annuals, perennials, herbs, and vegetables in pots need daily watering during summer’s heat. Succulents and cacti can go longer between thorough waterings. Adjust frequency as needed based on type of plant, pot size, weather, and soil moisture.
Do self-watering pots need daily refilling?
Self-watering pots with reservoirs can go 2-4 days between refilling depending on their capacity and the weather conditions. Check the reservoir daily to see if it needs a refill.
How often should I water potted plants if away for a week?
Arrange for someone to water your potted plants halfway through a weeklong absence in summer if possible. Using self-watering pots with large reservoirs can extend the time between waterings. Also clustering pots together reduces evaporation.
Should I water potted plants less in summer?
Most potted plants actually need more frequent watering in summer’s heat, not less. Exceptions are succulents and cacti. Check soil moisture levels daily and don’t let plants dry out completely.
Conclusion
Proper summer watering is vital for growing healthy outdoor potted plants. While specific needs vary, most require daily or every-other-day watering when it’s hot. Always check soil moisture rather than following a fixed schedule. Adjusting frequency based on weather changes will keep plants hydrated and happy all summer long.