Watering plants at the right time can mean the difference between healthy growth and dehydration during Spain’s summer heatwaves. Experts recommend a specific approach to keep gardens, terraces, and balconies thriving.
As Spain faces its first major heatwave of the summer, with the AEMET issuing high temperature alerts across much of the country, the question of when to water plants becomes more urgent than ever. For many, the timing of daily watering routines can determine whether their gardens, terraces, and balconies survive the season or succumb to heat stress.
Specialists in horticulture agree: the most effective time to water plants during extreme heat is early in the morning, before the sun gains strength. At this hour, soil temperatures are lower, evaporation is minimal, and roots can absorb moisture more efficiently. According to the Royal Horticultural Society, this approach allows plants to make the most of the water throughout the day, reducing the risk of dehydration as temperatures climb.
Morning vs. Evening Watering
While watering in the early morning is ideal, evening can serve as a backup if mornings are not possible. However, experts caution against wetting leaves and stems late in the day, especially in humid regions, as lingering moisture can encourage fungal diseases and pests. Directing water to the base of the plant is the safest method, ensuring roots receive the hydration they need without increasing disease risk.
Common Mistakes During Heatwaves
One frequent error during hot spells is watering lightly and often. Although it may seem logical to give plants small amounts of water multiple times a day, this practice can actually weaken them. Shallow watering encourages roots to stay near the surface, where soil dries out fastest. Instead, deep and less frequent watering helps roots grow deeper, making plants more resilient to drought and high temperatures. To check if another watering is needed, simply insert a finger a few centimeters into the soil—if it feels dry, it’s time to water; if it’s still moist, wait a bit longer.
Extra Care for Pots and Containers
Plants in pots, planters, and hanging baskets are especially vulnerable during heatwaves. With less soil to retain moisture and roots exposed to rapid temperature changes, these plants often require more frequent attention than those planted directly in the ground. The University of Minnesota recommends watering containers as early as possible in the morning and using methods that deliver water directly to the soil, such as drip irrigation or careful hand watering.
Applying mulch—such as pine bark, dry leaves, compost, or plant debris—around the base of plants can also help retain moisture and keep soil temperatures down. Grouping pots in partially shaded areas during the hottest part of the day offers additional protection, reducing water loss and heat stress.
Efficient Watering for a Hotter Climate
During a heatwave, the goal is not simply to water more, but to water smarter. Early morning remains the most effective time, while midday watering should be avoided due to rapid evaporation and reduced absorption. As climate patterns shift and heatwaves become more frequent in Spain, adapting watering habits is increasingly important for anyone hoping to maintain healthy plants throughout the summer.
For those new to gardening in Spain’s climate, understanding these principles can make a significant difference. As the country continues to experience hotter, drier summers, efficient watering is not just a matter of plant health—it’s a practical response to changing environmental conditions.
