From our perspective as daylilies, our most critical need during heat and drought is consistent moisture at the root zone. Our fibrous root systems are relatively shallow, spreading out horizontally to absorb water and nutrients from the top layer of soil. When the sun bakes the soil surface and rain stops, this top layer dries out rapidly, leaving our roots thirsty and stressed. Deep, infrequent watering is far superior to frequent, shallow sprinkling. A long, slow soak encourages our roots to grow deeper into the cooler, moister soil below, making us more resilient and self-sufficient. When you only wet the surface, our roots stay shallow and become even more vulnerable to the slightest dry spell.
If you could do only one thing to help us, applying a generous layer of mulch would be it. From our vantage point at ground level, a 2 to 4-inch layer of organic mulch, such as shredded bark, wood chips, or straw, is like a life-saving blanket. It performs several vital functions directly for our root system. First, it dramatically reduces water evaporation from the soil, meaning the water you provide stays available to us longer. Second, it acts as a powerful insulator, keeping the soil temperature significantly cooler on blistering hot days. Hot soil stresses our roots and can inhibit their function. Finally, as the mulch slowly decomposes, it enriches the soil, creating a better environment for us to thrive in the long term. Please keep the mulch a few inches away from our crowns to prevent rot.
Our leaves are our solar panels, but they are also the primary site for water loss through transpiration. In extreme heat, we can lose water faster than our roots can absorb it, leading to wilting, scorched leaf tips, and reduced energy for blooming. While you should never remove all our foliage, you can help us by strategically removing spent flower scapes (stalks) once all the buds have bloomed. This eliminates a major drain on our water reserves. If a severe heatwave is forecast, you can also consider a "hard cutback." This involves cutting our foliage back by about half. This is a drastic measure, but it immediately reduces our leaf surface area and thus our water loss, allowing us to conserve energy and survive the stressful period. We will put out fresh new growth when cooler, wetter conditions return.
The timing of your watering deeply affects how efficiently we can use it. Watering us in the heat of the midday sun is highly inefficient. A significant amount of water is lost to immediate evaporation before it even reaches our roots. Furthermore, water droplets on our leaves can act like tiny magnifying glasses in intense sun, potentially causing leaf scorch. The ideal time to water us is in the early morning. This allows water to soak deep into the soil with minimal evaporation, and any moisture on our leaves has time to dry before the sun reaches its peak, reducing the risk of fungal diseases. Evening watering is our second choice, but wet foliage overnight can sometimes encourage mildew.
Our ability to withstand drought begins long before the drought itself, with the health of the soil we live in. Amending the soil with generous amounts of organic matter, like compost, is like building a sponge beneath us. This organic matter helps the soil retain moisture and improves its structure, allowing our roots to penetrate more easily. When it comes to feeding us, a balanced, slow-release fertilizer applied in early spring is best. Please avoid high-nitrogen fertilizers during hot, dry periods. They encourage a flush of soft, succulent growth that is particularly vulnerable to heat stress and water loss, ultimately weakening us when we need to be strong and conservative with our resources.
