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Tag: Water Wise Gardening

Protect Plants from Summer Heat in Four Steps

A thick layer of straw helps hold moisture around these okra plants while also keeping walkways clean and weed free.
A thick layer of straw helps keep roots cool while also holding moisture and keeping walkways clean and weed free.

It’s baking hot and your garden plants are wilting, waning, and altogether looking crummy. What do you do? High heat can take a toll on our vegetable and flower gardens, causing fruit and flowers to drop, buds to shrivel, leaves to wilt, and plants show general stress. It’s bad news, but there are a few protective measures gardeners can take to save their green investments through the worst of the high heat periods. Just four tips can help you turn your over-heated plants around: 1. Plant Smart, 2. Add Water-Holding Amendments, 3. Water Smart, and 4. Provide Mulch and Shade.

Plant Smart

Profusion Zinnias
Heat-tolerant Profusion Zinnias buffer the hot edge of a driveway garden.

This basically means choosing heat-tolerant plants and picking the right locations for your plant choices. Vegetables (read more about heat-tolerant vegetables here and read more about heat-tolerant greens here) and flowers (read more about heat- and drought-tolerant bedding flowers here) that can take the heat generally originate from warmer parts of the world. Choosing a Mexican-native Marigold (Tagetes erecta) over a European Pot Marigold (Calendula officinalis) means a world of difference when temperatures heat up. The Mexican Marigold will thrive and the European species will fry.

Mexican marigolds
Choose heat-tolerant plants, such as Mexican marigolds, that will shine all season long.

More heat-tender plants should be placed in spots where they are protected by midday shade. Those planted alongside pavement need to be tougher because of the reflective heat generated by the concrete or asphalt. Buffering walkway or driveway edges with super tough creeping plants, such as rocky stonecrop (Sedum rupestre ‘Angelina’), trailing rosemary (Rosmarinus officinalis ‘Prostratus’) or Profusion zinnias, will reduce some of the glare and generated heat. Another tip is to place plants so that they are just touching, but not overcrowded. Keeping the sunlight from hitting the ground surrounding plants is cooling. It is also smart to plant from high to low with taller plants shading shorter plants (Wild Senna is an outstanding tall, heat-tolerant perennial you can read about here).

Add Water-Holding Amendments

Fafard Premium Natural & Organic Compost Blend packWater keeps soil cooler, so adding water-holding amendments helps reduce heat stress as well as drought stress. Organic matter always holds more water, so it is wise to add fresh compost to beds before planting. Fafard Premium Natural & Organic Compost is a great choice, but there are other amendments designed specifically to hold water. A sustainable selection is Black Gold Just Coir, which is comprised of 100% all-natural coconut coir and holds water like a dream. Coir comes from processed coconut husks, a byproduct of the coconut industry.

Water Smart

Silver watering can
Early morning is a great time to water plants, if the day is going to be a hot one.

There are several watering techniques that will help you protect your plants from heat a little better (read all about smart watering tips here). First, watering early in the morning or later in the evening will allow plants take in moisture at cooler times of the day to help them withstand the high heat of midday. I like to water in the morning best. Drip hoses also help keep roots cool and water directly at the root zone.

Provide Mulch & Shade

Mulching
Mulching cools rootzones, which helps keep plants happy during the hottest times of the day.

Mulches help keep plant roots cool. In the garden, lighter mulches, such as straw, hay, or leaf mulch, make a real difference in keeping plants happy during high-heat windows. Leaf mulch or pine straw are good choices for ornamental gardens. When days are really scorching, vegetables may benefit from floating shade cloth to reduce the sun’s glare. The cloth can either be supported by stakes surrounding beds or floated over rows during the day’s hottest window, from 11:00 am to 5:00 pm. Most studies show that the time between 2:00 and 3:00 pm is the hottest time of the day.
The most scorching days of summer usually don’t last long, but they can do lasting damage, dulling your garden’s looks and reducing yields. Protect them during these times to make the most of your garden for the rest of the season.

Waterwise Container Gardening

Waterwise Container Gardening Featured Image

Container plantings are notorious for drying out quickly and needing extra water through the worst summer months, lest they dry and shrivel in a day’s time. Miss one morning watering and the most beautiful contained petunias or impatiens can go from great to ghastly full wilt by evening. Thankfully, there are ways to reduce the need for daily container watering while also ensuring lots of pretty potted plants for porch and patio.

The four factors to consider when designing water-wise container gardening are 1. pot size and type, 2. soil and soil additives, 3. plant drought tolerance, and 4. pot placement. Get these factors right and your containers may require half the water normally supplied to summer pots.

Container Size and Type

Flowers in clay pot
Glazed and plastic pots hold water better than terracotta. (Image care of the National Garden Bureau)

Container size and type are things that most gardeners don’t consider as water-saving, but the larger and more water-impermeable the pot, the more it will conserve water. Think about how plants move water. They take it up through the roots, the water travels through the plant, and then it’s released from tiny pores in the plant’s leaves and stems. Basically, the plant pulls water from the soil. A larger pot holds more water and provides more root space—offering a bigger well of needed moisture. And, an impermeable pot surface simply means that less water will be lost due to evaporation. Terra cotta pots are the worst when it comes to evaporation while glazed ceramics and plastic or resin pots keep water at the root zone.

 Soil and Additives

Fafard Ultra Container Mix with Extended Feed and RESILIENCE pack

Some soils and amendments like peat moss hold water well and others like perlite encourage drainage. Our best water-holding potting soils contain lots of rich organic matter in addition to water-reserving additives, such as the Moisture Pro™ water-holding crystals Fafard® Ultra Container Mix with extended feed and RESiLIENCE®. The RESiLIENCE® additive, which is OMRI-listed for organic gardening, helps plants further by helping plants reduce water stress during hot, dry times. The addition of coco coir (we recommend Black Gold Just Coir) or Fafard Canadian Sphagnum Peat Moss further enhanced water-holding to reduce the need to water every day.

Drought-Tolerant Plants

Lantana camara Bandana Rose
Lantana camara BANDANA™ ROSE

There are so many beautiful container-friendly garden flowers that stand up to heat. For containers, it’s great to choose heavy-flowering annuals that look nice until frost—either with their foliage, flowers, or both. It’s also nice to try new garden center offerings, in addition to solid standbys, that will wow and impress.

For warm container color, try the new Bidens Campfire® Fireburst with its tiny hot daisies of orange-red and gold. Annual Bidens bloom continuously and look great alongside the red and orange flower of Lantana Rose Bandana, and gold-, -orange, and magenta-flowered Zinnia Pinwheel Mix, which are also compact. All stand up to hot, dry weather once established.

Pennisetum glaucum 'Jade Princess'
Pennisetum glaucum ‘Jade Princess’

The outstanding Cuphea Vermillionaire® is another super tough, super pretty bloomer producing lots of orange-red, tubular flowers through summer that attract hummingbirds. These glow container plantings when placed alongside tall, Angelonia Angelface® Superwhite and soft, airy Mexican hairgrass (Nasella tenuissima). Another great hummingbird flower for heat and containers is the new Salvia Ablazin’™ Tabasco with its taller stature and scarlet flowers that shine alongside the chartreuse leaves and purple plumes of Pennisetum glaucum ‘Jade Princess’.

Containers of bold succulents are also welcome for those wishing to water as little as possible. Pots of colorful Agave, Aloe, cacti or sedums look great through summer and can be brought into a sunny indoor spot through winter. The only caveat is that these plants tend to want a better-drained soil, such as Black Gold Cactus Mix.

Container Placement

Pink Pentas and purple Pennisetum with butterfly
Pretty pink Pentas and purple-leaved Pennisetum are both drought resistant and look great in containers.

Where you place your plants can make a big difference in how quickly they lose water. Exposed areas with hot sun and wind will always dry plants out more than protected areas shielded from the wind and sheltered from the sun during the hottest time of day. Morning and afternoon sun is always less beating, so place planters in spots where this level of sun dominates and light shade it provided around noon.

Planning ahead with these four steps for water-wise containers will save water, time, and headaches through summer. Your containers will still need regular care and water for the best health and looks, but you will be able to enjoy them more and worry less about summer container instant-wilt.