Summer is here, and all over the globe people are experiencing above average temperatures. Areas that normally have warm summers are having Sahara-like conditions with low rainfall and high heat.
Many of us are having 90° to well over 100°F (32° to 38°C) days and very warm nights. Because of this, many of our normal colorful summer annuals have faded in their vigor and beauty.
The good news is that while many plants and flowers seem to be fainting away, there are others that sing merrily along through the mid-summer heat.
The tough-as-nails flowering plants that we are going to share with you will provide the color you want, while tolerating the most intolerable summer heat. And more good news, we are going to give you many more ideas than just your regular zinnias and marigolds that are always mentioned in warm weather flower articles, because we want you to have more options and better choices.
So without further ado, here are more than 25 suggestions to replace stressed and faded plant material in your landscape that will also conserve water, while looking like a million dollars in full, hot sun.
Table of Contents
- First Some Preparation
- Add Organic Matter
- Buy Quality
- African Daisy (Arctotis)
- Bitterweed (Hymenoxys odorata)(Tetraneuris)
- Blanket Flower (Gaillardia pulchella)
- Butter Daisy (Melampodium paludosum)
- Cockscomb (Celosia cristata)
- Coleus 'Big blonde'
- Cosmos bipinnatus and C. sulfureus
- Dahlberg Daisy (Dyssodia tenuiloba)
- Dusty Miller (Senecio cineraria)
- Fanflower (Scaevola aemula)
- Gazania (Gazania rigens)
- Globe Amaranth (Gomphrena globosa)
- Helenium 'Dakota Gold'
- Mexican Sunflower (Tithonia rotundifolia)
- Moss Verbena (Verbena tenuisecta)
- Phlox 'Intensia'
- Rose Moss (Portulaca grandiflora)
- Summer Snapdragon (Angelonia)
- Sunflower (Helianthus annuus)
- Sweet Potato Vine (Ipomoea batatas)
- Texas Bluebells (Lisianthus /Eustoma)
- Vinca (Catharanthus roseus)
- Wishbone Flower (Torenia)
- Zinnia elegans
First Some Preparation
Very quickly, before we get into the plants themselves, we first need to mention that all plants no matter what their environment, will always do better when the soil is prepared properly beforehand.
That said, many of the plants in this article perform very well in poor soil, but to get off on the right foot, do a little soil prep first if you can.
Add Organic Matter
Even though these plants can take high heat and are drought tolerant they will do even better with some organic matter worked into the soil first.
Organic matter helps to retain moisture plain and simple.
Make sure you buy healthy looking plants. Plants that are stressed from the start can’t withstand the heat as well as they could, so purchase quality plants.
You knew this one was coming didn’t you? Probably saw it a mile away. If you have been reading this magazine for any length of time, we are big on the mulching thing – because it works.
Mulch not only retains moisture, but helps keep the soil cooler. If however you’re not sure about mulching, make sure you read our Complete Guide On How To Use Mulch:
Ok – with that out of the way – the following plants can take:
90° to over 100°F (32° to 38°C) days
All zones *
* All zones because these flowering plants whether they are annuals, perennials, or biennials are being treated in this article as warm-season annuals only.
* All zones because while these flowers can take high heat and dry conditions, they will also do well in warm to mild summer areas as well. They are very versatile plants.
African Daisy (Arctotis)
Plants originated in southern Africa. Arctotis species have lobed leaves that are rough, hairy. or woolly. Their flower heads usually have a contrasting ring of color around their central eye. Come in a variety of colors: white, pink, orange, yellow, and red.
Low growing, plant for mass color, 2 plants can quickly cover an entire planter bed. Beautiful for the border where the flowers are produced in profusion throughout the summer, and excellent for cutting. Silvery/green finely cut foliage. Flowers mid summer to frost.
Bitterweed (Hymenoxys odorata)(Tetraneuris)
A Texas native. Golden yellow flowers on stems to 1 feet (.3 m) high. Narrow, grassy, aromatic leaves form small tufts about 8 inches (20 cm) tall and 1 foot (.3 m) wide.
Somewhat similar to thrift (Armeria) in appearance. Flowers have rays with notched edges. Attractive in containers. Plant always flowers even in full 100°F (38°C) sun; it doesn’t care, it will grow in a crack in the concrete!
Blanket Flower (Gaillardia pulchella)
This is an annual gaillardia. It is a low-growing, colorful plant in warm colors that appears fringed. Stems are single and arise from a taproot. Plant is 1.5 to 2 feet (.45 to .61 m) tall and 1 ft. (.3 m) wide. Flowers come in warm shades of red, yellow, and gold. Easy to grow. Come in single and double flowered varieties.
Butter Daisy (Melampodium paludosum)
This annual grows from 8 to 24 inches (20 to 60 cm) tall, with equal spread, and produces abundant yellow daisy-like flowers. It does best in full sun and well-drained soil. It excels in the heat and dry conditions of the summer. Very easy to grow.
Cockscomb (Celosia cristata)
Celosia cristata ‘Armor’ series, doesn’t have the side branching ability of other celosia, but it makes 1 giant, crested flower. It will get 2 feet (.61 m) across and about 2 and 1/2 feet (.61 to .76 m) tall. It likes full sun. They come in red, purple, orange, and yellow.
A great tip for celosia: don’t buy them when they are root bound in the pot, so check carefully before you buy. Once they get root bound, they don’t grow back out.
Coleus 'Big blonde'
This coleus, believe it or not, will take 107°F (42°C) full, hot sun. They grow these in eastern Texas quite abundantly. They can tolerate low humidity or high humidity, it doesn’t matter.
A very tough plant, is has bold chartreuse leaves with dark magenta stems. It gets 24 to 36 inches (60 to 91 cm) tall and 12 to 14 inches (30 to 36 cm) wide.
Cosmos bipinnatus and C. sulfureus
Cosmos grows best in the worst conditions – hot and dry. This is why cosmos is one of the best possible annuals for tough to grow climates like Texas, Georgia, and Arizona. It comes in an abundant varity of sizes from dwarf that are only 4 to 8 inches (10 to 20 cm) tall, to medium that are 12 to 24 inches (30 to 60 cm) tall, to very tall that are 2 to 3 feet (.61 to 1 m) tall. It makes a good cut flower, and re-seeds readily.
Comes in many flower colors such as Picotee, Red, White, Yellow, Gold, Crest Red, Candy Stripe, Pink, Dark Pink, and more. The are profuse bloomers and always covered in flowers.
Dahlberg Daisy (Dyssodia tenuiloba)
Dahlberg daisies have dainty yellow flowers and thrive in hot conditions in full sun. They grow to approximately 6 to 8 inches (15 to 20 cm) tall and as wide.
They have thread-like, aromatic foliage that is mostly hidden by masses of daisy-like, golden-yellow flowers on these low annuals. Good edgings for borders and colorful additions to rock gardens. Excellent cut flowers.
Dusty Miller (Senecio cineraria)
Dusty miller makes an attractive foliage plant that works well in the garden and its grey foliage makes it a good plant for bringing other plants together. Grown as annuals these plants have very decorative silver leaves that are finely divided. They come in many varieties.
Fanflower (Scaevola aemula)
This plant is from Australia; some forms are prostrate, others upright to 2.5 feet (.76 m) tall. Flowers are all along the branches. Most are familiar with the big new ‘Blue Wonder’, it has a bigger flower, which is great in hanging baskets.
But for a bedding application or a small pot this blooms more frequently, stays more prostrate, is nice and compact. You will get your money’s worth in 1 season of bloom because it blooms its head off!
Gazania (Gazania rigens)
This bright trailing annual comes in a host of colors. Gazanias are tender perennials grown as an annual in harsher climates. The flowers close at night.
Globe Amaranth (Gomphrena globosa)
Annual plant from Central America. The rounded flowers of the globe amaranth look like brilliant purple clover, though it may come in other colors such as white, pink, and lavender.
As well as being a tough survivor in the heat, globe amaranth makes a good plant for drying. Stiffly branching plants to 2 feet (.60 m) tall and 1 foot (.3 m) wide. Profuse bloomers.
Helenium 'Dakota Gold'
Was given the Flameproof Award in Texas for withstanding high heat with flying colors! This is a rather coarse looking plant, but a profuse bloomer. Numerous leafy stems have great sheaves of dasiy-like flowers.
Typically brown-centered flowers with yellow, orange, red, or copper rays. Come in wide variety of sizes. In some varieties, the ray flowers are reflexed.
Lantana ‘New Gold’ loves 100-degree heat and needs little water, and blooms solidly through the summer.
Other lantana varieties such as Lantana camara hybrids are fast growing and are valued for a profuse show of color over a long season.
Comes in a wide variety of size and colors. Shrubby kinds are good for low hedges, or annuals in beds or containers. Spreading kinds are excellent ground covers.
Mexican Sunflower (Tithonia rotundifolia)
Native to Mexico and Central America this plant has velvety green leaves and spectacular, gaudy flowers. Grows quickly to 6 feet (2 m) tall and 4 feet (1.2 m) wide. Flowers have orange-scarlet rays nd tufted yellow centers. Can be used as a temporary screen.
Moss Verbena (Verbena tenuisecta)
From South America, grows 6 to 12 inches (15 to 30 cm) tall and 2 to 5 feet (.61 to 1.5 m) wide. Finely cut dark green leaves, with blue, purple or violet flowers. ‘Alba’ is white flowered.
Its low-growing , spreading growth makes it an ideal drought-resistant ground cover. Moss verbena establishes easily and tolerates poor soils and drought. Makes a great nectar plant for butterflies and honeybees.
This plant was bred from 2 varieties of Phlox, one a Texas native from Padre Island. It starts flowering about March and will bloom until July. It will then rest, then bloom again. Some have said theirs just flowered to death, which it does here occasionally.
For 6 months of heavy blooms you can’t beat it. It’s a bouquet in the garden. Grows 10 to 12 inches (25 to 30 cm) tall and as wide. Comes in light pink, white, lavender, lilac, neon pink, dark pink, and striped. Attracts butterflies.
Rose Moss (Portulaca grandiflora)
Rose moss is very tolerant of summer heat. It is a low growing, succulent plant that comes in an array of bright and intermediate shades of red, rose, pink, orange, white, and yellow. Comes in single or double flowered varieties. Grows to 6 inches (15 cm) tall and 1.5 feet (.45 m) wide. Flowers shaped like mini roses.
Summer Snapdragon (Angelonia)
This plant looks like a mini snapdragon or delphinium. Showy 8 inch (20 cm) tall spikes come in small blue, purple, pink or white flowers. Spikes appear on top of plants that are 1 to 1.5 feet (.3 to .45 m) tall and as wide. Excellent bedding plant, also good in containers. Long lasting cut flower.
‘Serena white’, the best Angelonia on the market , in 107°F (42°C) weather, in full sun, the white flowers look perfect and clean, it never turns brown, is always in flower, doesn’t flop and doesn’t need staking.
Sunflower (Helianthus annuus)
The familiar yellow giant, the sunflower, can grow to 10 feet (3 m) or taller and makes a striking backdrop. Other varieties are dwarf, only growing to 10 inches (25 cm) tall. Many varieties come in orange and reddish hues with single or double-fluffy flowers such as ‘Teddy Bear’.
Sweet Potato Vine (Ipomoea batatas)
A wonderful, tough plant grown for its foliage. Tuberous roots with a trailing habit. Has many fancy-leafed forms that vary in size: from 2 to 4 inches (5 to 10 cm) long, and in shape: from heart shaped to deeply lobed.
Comes with many different leaf colors: purple, black, medium green, burgundy, golden-green, and white-pink variegation. Attactive as hanging baskets.
Texas Bluebells (Lisianthus /Eustoma)
Native to the high plains, plants grow better where nights are warm. Grown as a cut flower for its long stems.
A 1 foot (.3 m) wide clump of gray-green foliage sends up 1 to 3 feet (.3 to 1 m) tall stems topped by tulip-shaped flowers that come in purple-blue, pink, or white. Flowers all summer long if old flowers are cut off. Comes in single or double flowered forms.
Vinca (Catharanthus roseus)
Thrives in hot, dry or humid climates. Glossy green leaves cover a bushy plant 1 to 2 feet (.3 to .61 m) tall and as wide. Flowers in pure white, white with rose, blush pink, or bright rose. Flowers all summer long. Comes in both upright and prostrate forms.
Wishbone Flower (Torenia)
This is normally a shade plant, but it is grown in Texas in full sun, in 107°F (42°C) heat and yet this plant does just fine. There is the Moon series which is more bushy and upright to 1 foot (.3 m) tall and as wide; The Summer Wave series is a trailing type and is also great in full sun.
They’ll mound up, if they get too tall, just cut them down. Torenia fournieri ‘Purple Moon’ and the new Torenia fournieri “Golden Moon’ is a lovely yellow and purple combination. It is a great plant for full sun or shade, hanging baskets or containers. It’s like a flowering Kudzu.
Zinnias are colorful, easy to grow, and attract birds and insects, including butterflies and hummingbirds. Swallowtail, Monarch, Painted Lady, and other butterflies enjoy the flowers’ nectar. Hummingbirds eat up the tiny insects drawn to the flowers. Sparrows, goldfinches, and other birds gobble the zinnia’s seeds.
‘Distance Mix’ is early blooming, more heat tolerant, and around 12 to 16 inches (30 to 40 cm) tall. The colorful flowers, at most 3 inches (7.6 cm) wide, range from yellow to cherry to white and are semi-double to double flowering.
Zinnia, the Profusion series, is a narrow leaf zinnia that is an 18 inch (46 cm) mounding plant that blooms constantly with orange, red, orangish-red, white or pink flowers. The pink is the only one of the series that isn’t any good because as soon as it turns 90°F (32°C) its flowers fade out.
If in the past, during the hot summer months, you felt you couldn’t plant anything that would last, well now you have more than 25 plants to choose from. That’s pretty rich I’d say!
All of the above plants are also miserly with the water, so your water bills won’t be through the roof, which also a very good thing.
Many of the these plants may be new to you, others may not, but they are all tough yet easy to grow.
And as said in the introduction all these plants can take the heat, but they also do fine in warm to mild summer areas too, so even those of you who don’t live in climates that don’t get prolonged heat, you can use these plants successfully as well.
Now go get some iced tea and figure out what you’re going to plant!
The writer is a member of the National Garden Writers Association, a nationally published writer, and a certified organic grower. She regularly speaks and writes about all gardening related topics, with an emphasis on making gardening a successful and enjoyable process for anyone who wants to learn. Weekend Gardener Monthly Web Magazine concentrates of giving detailed gardening tips to all levels of gardeners.