How Do You Keep Plants Cool in Heat Waves?

“The summer has been hotter than it’s ever. How can I protect my plants from the severe heat?” Angie of Atlanta, Georgia

Answer: Georgia summers are notoriously hot. Being faced with temperatures well over 95 degrees F for days on end is a trial. Here are some ways to help protect your plants, especially those that are less heat tolerant. Specimens planted in full sunlight during the hottest times of the day (around 2:00 pm to 4:00 pm) need the most protection.

Four Ways to Cool Plants in High Heat

  1. Irrigate plants very well in the early morning. If temperatures exceed 100 degrees F, water again in the evening after the sun has fallen.
  2. Protect plants that are in full sunlight with floating row covers fitted with white shade cloth. These covers are easily placed over plants and removed. You can also simply purchase shade cloth and drape it over highly exposed plants. Both methods help. Gardeners in your area have also informed me that they have been moving patio umbrellas around their yards to shade their most prized plants. (One even said that her neighbor did not, and it resulted in some substantially fried rhododendrons and hostas.)
  3. Move containers into shaded areas or indoors during the most dangerous heat and water twice daily.
  4. Opt for lightweight, light-colored mulches. A cooling layer of straw around vegetable roots will protect plants from heat, and long-fibered sphagnum peat moss makes a good, cooling cover for shade beds and containers. (Click here to learn about more mulch options.)

I also want to note that pets and wildlife also feel the stress. Leave water out for the animals and keep your pets from going outdoors for extended periods and walking on hot surfaces (grass only!). I also recommend that you read the following two garden articles for more helpful tips.

Cool Gardens: Designing for Summer Temperature Control

Nine Water-Saving Garden Tips to Fight Drought

Stay cool and happy gardening,

Jessie Keith

Grower’s Gold Horticulturist

How Do You Save Heirloom Pepper Seeds?

“I would love advice on saving seeds off of heirloom bell peppers.” Question from Amy of Lewiston, Idaho

Dear Any,

I have good news! Peppers are some of the easiest seeds to save because peppers are dry, rather than fleshy, fruits with open interiors. The seeds are easy to gather from the ripe fruits.

What is important is waiting until the fruits are ripe to harvest the seeds. Green peppers have immature seeds that will not germinate, so wait until the peppers have developed full color. Once the fruits are fully colored and ripe, the seeds will be ripe.

Collect the seeds, place them in a labeled packet, and store them in a cool dry place through winter. I generally start my peppers in late winter or spring, at least 8 weeks before the last frost date.

Please watch the video below for tips about how to grow peppers organically!

Happy gardening,

Jessie Keith

Grower’s Gold Horticulturist


What Are Compact Sun-Loving Flowers For Containers?

“I have full sun in the front of my home, and I want to put up large containers in the front of my house, but I’m not sure what plants would work. Help! Thank you.” Question from Melissa of Lansing, Michigan

Answer: There are lots of great plants for sunny containers. Good options do not get too tall or wide and grow and flower well in small spaces. For design purposes, plant them in contrasting combinations with bushy and trailing or spilling plants in complementary colors. Annuals are most often used in pots. Here are some that will grow beautifully in Lansing, Michigan.

Favorite Bushy Bloomers for Containers

Summer Snapdragon (Angelonia angustifolia hybrids). Choose these heat lovers for sunny pots. They even take drought. Some of the newer summer snapdragons, like those in the Angelface® Cascade Series, are a bit more compact, making them ideal for containers.

Bidens (Bidens hybrids): These heat-loving annuals generally have yellow or orangish-red daisy-like flowers. Most varieties keep on flowering until fall.

Geraniums (Pelargonium hybrids): Old-fashioned geraniums need to be deadheaded, but they are classic container plants that keep looking great until frost. I love cherry-red varieties, but you can also find them with white, pink, salmon, orange, or orange-red blooms.

Petunias and Calibrachoa (Petunia and Calibrachoa hybrids): Go to any garden center, and you will find loads of petunias and calibrachoa. Vista Petunias and Superbells Calibrachoa are my favorites. They bloom beautifully from summer to fall and trail nicely in containers.

Profusion Zinnias (Zinnia Profusion Series): Here is one of the best trailing zinnias for nonstop flowers for the sun. They come in lots of colors, including white, orange, yellow, and red, and they are very easy to grow from seed. (Click here to learn how to grow annuals from seed.)

Favorite Sunny Trailers for Containers

Dichondra Silver Falls (Dichondra argentea Proven Accents® Silver Falls): Here is one of the easiest, prettiest, most drought-tolerant spillers that you can grow. Its trailing stems of pure silver cannot be beaten.

Mexican Hair Grass (Nasella tenuissima): Plant this fine, fountain-shaped, airy grass to add height and spill to containers.

Ornamental Sweet Potato (Ipomoea batatas ornamental hybrids): There are loads of compact, trailing ornamental sweet potatoes that really light up containers. Two great, compact options are the bright green Sweet Caroline Medusa Green and variegated green, white, and pink Tricolor

Bacopa (Sutera cordata hybrids): These small-leaved, trailing annuals have small, pretty flowers of white or lavender pink. Of the white-flowered varieties, Snowstorm® Giant Snowflake®  has the largest flowers and a great spilling habit.

Annuals grow beautifully in Grower’s Gold potting mix. Then be sure to feed the pots with slow-release fertilizer and water-soluble fertilizer for consistent strong growth and flowering.

I hope that some of these plants interest you.

Happy gardening,

Jessie Keith

Grower’s Gold Horticulturist

Why Are My Tomato Leaves Curling?


Upward curling tomato leaves indicate stress more often than disease.

“My tomato plants have leaves curling upwards along the edges. Why?” Questions from Andy of Zionsville, Indiana

Answer: Based on your photo, your leaf curl appears to be caused by something in the environment rather than a disease. There is a Tomato Yellow Leaf Curl Virus, but your plant does not appear to have several of the symptoms, such as stunting, yellowing, and leaf browning. Tomato plants, like yours, more commonly experience physiological leaf curl when subjected to various environmental stresses. Here are four possible sources of stress able to cause leaf curl.

Environmental Tomato Leaf Curl Causes

  1. Water stress (too little or too much water) — Vines fail to grow as well when water is lacking, and they develop root rot when there is too much water. Either problem can cause leaf curl. Provode plants with regular, even watering for best growth.
  2. Heat stress — Temperatures over 85 degrees F can cause some tomato plants stress, resulting in leaf curl. Some tomatoes are more heat-tolerant. Two good heat-tolerant varieties are the large, red-fruited ‘Heatmaster‘, which can take the high heat of the South, and disease and heat-resistant ‘Heatwave II‘, which bears deep red tomatoes with good flavor.
  3. Wind stress — High winds can cause rapid water loss from the leaves. Leaf curl can result.
  4. Herbicide damage – Glyphosate herbicide damage is most common and can cause leaf curl if a small amount reaches your tomatoes from a upwind application.

Could any possibilities be the cause? Please let me know. In the interim, click here to read more about leaf curl, and watch the video below about growing flawless tomatoes!

Happy gardening!

Jessie Keith

Grower’s Gold Horticulturist