25. HOT WEATHER FLOWER GARDEN TIPS

Hot weather can strain our passion for flower gardening. Both the flowers and the gardener may start to look stressed and bedraggled in the heat. But you can have a flower garden that thrives in a hot, sunny area if you take certain steps to ensure its success. The first step is to consider the weather of the entire season. Resist the urge to buy or seed dainty spring flowers in the cooler time of year if you know it is going to get much hotter later on. Always remember the dog days of summer are around the corner! This is hard to do, I know, when that multicolored ruffled spring pansy is calling your name . . .

There are many annuals or perennials to choose from that are sun and heat tolerant. For example, zinnias, native to Mexico, are reliable annual flowers for a sunny spot. They bloom in vivid colors in the summer. And established zinnias are almost drought tolerant! Likewise, the deer-resistant perennial red hot poker plant (Kniphofia uvaria) loves full sun and poor soils. They are suitable for USDA hardiness zones 5–9. And try the 10-inch-tall ‘Arizona Sunset’ hyssop (Agastache aurantiaca ‘Arizona Sunset’), a perennial, with its minty fragrance. Goldfinches love the seed.

Another tip is to water your flower garden often and deeply during the heat of the summer. The key is to make sure the soil (not the flowers!) is fully moist. As I often say, it is the roots in the soil, not the flower petals, that need the water. Do not pass the hose rapidly over the flowers—you are simply watering the flower petals—it does nothing for your plants. And it’s wasteful, because some of the water will simply evaporate. It is better to give the soil that the flowers are growing in a very thorough soaking. Connect a nozzle to your hose, turn it to the shower setting for a rain-like spray, and set it at the base of the plants. Let the water soak deeply into the earth. Do this two or three times a week. This is more effective than a quick spritz every day.

If your flowers are not particularly heat tolerant, they will appreciate a light misting of water in the air on a hot day. The mist cools down the sprayed area as it evaporates. So, for delicate flowers, set your hose nozzle on the mist setting and spray the air around them on a hot afternoon. Take care to do this well before evening, because the water may not evaporate later in the day and mildew can occur. By the way, misting will cool you down, too!

Mulching can help some woody perennials like Russian sage or lavender, but I do not mulch herbaceous flowers. Cover the soil with a thin layer of good organic mulch, such as finely ground bark or pine needles, around woody-stemmed flowers. This acts like a blanket between the soil and the hot sun and also helps to keep water in the ground.