Blossoming Beauties: 5 Summer Annuals for Your Sunny Colorado Garden

Are you ready to add a burst of vibrant color and charm to your sunny Colorado garden this summer? Look no further than these five popular annuals, each handpicked to thrive in the sunshine and liven up your outdoor space. From bold hues to delicate petals, these summer stars are sure to dazzle your senses all season long.

(Zinnia elegans)

Zinnias are the epitome of summer cheer, boasting a rainbow of hues ranging from fiery reds to sunny yellows and soft pinks. These hardy annuals thrive in full sun and well-drained soil, making them a perfect choice for beds, borders, and containers. One of the best features of zinnias is their long-lasting blooms, which attract butterflies and pollinators, adding life and movement to your garden. Whether you opt for compact varieties like ‘Profusion‘ or towering giants like ‘State Fair,’ zinnias are sure to steal the summer show with their vibrant colors and effortless charm.

(Tagetes spp.)

Marigolds are beloved for their cheerful blooms and pest-repelling properties, making them a must-have for any summer garden. These sun-loving annuals come in a variety of sizes and colors, from compact orange ‘French Marigolds‘ to tall and stately ‘African Marigolds.’ Not only do they add a bright pop of color to your garden, but they also help deter pests like aphids and nematodes, making them excellent companions for vegetables and other plants. Plus, their spicy fragrance adds an extra layer of charm to your outdoor space, making them a favorite among gardeners and pollinators alike.

(Cosmos bipinnatus)

If you’re looking for a carefree and whimsical addition to your garden, look no further than cosmos. These dainty annuals boast delicate, fern-like foliage and an abundance of daisy-like flowers that dance atop slender stems. Cosmos thrive in full sun and poor soil, making them an ideal choice for Colorado’s challenging growing conditions. Whether you choose classic white ‘Sensation‘ or vibrant ‘Sonata Red Shades,’ cosmos are sure to add a touch of ethereal beauty to your garden while attracting butterflies and beneficial insects.

(Petunia x hybrida)

Beloved by gardeners for their vibrant colors and versatility, they will thrive in Colorado’s summer temperatures. With hues ranging from delicate pastels to bold jewel tones, these annual flowers add a burst of color to any garden or container. They are low-maintenance, requiring only ample sunlight and well-drained soil to flourish. Their cascading habit makes them perfect for hanging baskets, while compact varieties are ideal for borders and edging. Additionally, petunias attract pollinators like butterflies and hummingbirds, enhancing biodiversity in the garden. With their long-lasting blooms and easy care, it’s no wonder these vibrant plants remain a staple for Colorado gardeners seeking plenty of bright summer colors.

(Verbena x hybrida)

For cascading color and continuous blooms all summer long, look no further than verbena. These trailing annuals are perfect for hanging baskets, containers, or spilling over the edges of beds and borders. Verbena’s clusters of tiny flowers come in a range of shades, from soft pastels to vibrant jewel tones, attracting butterflies and hummingbirds to your garden. Plus, verbena is heat and drought tolerant, making it an excellent choice for our sunny and arid climate.

These five popular low-maintenance annuals are sure to add beauty, color, and pollinator-friendly blooms to your summer garden. Whether you’re a seasoned gardener or just starting out, these versatile plants are guaranteed to thrive and bring joy to your outdoor space all season long.

Hardening Off Annuals


The gradual process of hardening off is a crucial one, like the slow but steady  way we brace our entry into a chilly lake in summer. Jumping in all at once is a shock to our system, but if we start by sticking a toe in and slowly working our way in, the total immersion is not nearly so stressful.

Plants need a period of time to get used to their new homes.  The adjustment period is called “hardening off.”  We recommend a hardening off period of about three to five days.  This will give the foliage tissue time to toughen up so the plants don’t go into shock.


1.   Put new plants outside in a place that is protected from sun and wind.  Make sure they get watered as needed.

2.   If nights will be cooler than 38-40 degrees, bring into the garage or house.

3.   Move the plants out a littler farther each day toward the place in which they will be growing.

4.   Leave the plants out at night unless there will be low temperatures.  They still might need covering at night if there is a drastic change in the weather.

5.   Plant on a cloudy day and they will take right off.  Using a root stimulator when planting will help.


The process above can be sped up, but it is basically the same.


The process here is somewhat different since you are acclimating your plants to hot sun and drying winds.

1.   Put plants in a cool, protected place for a day or two.

2.   Gradually move plants towards their new location over a period of three or four days.

3.   Plant in the cool of the evening or on a cloudy day.

4.   Be prepared to shade with a shingle or board until plants are settled in.

5.   Water as needed.  Always check the soil first.

Nurturing Houseplants in Winter

Now that our doors and windows are closed for the winter, houseplants provide a welcome splash of life and color in our indoor landscape.

Fresh, vibrant, and green, those innocent looking houseplants contribute much more than just a touch of color though. They play a significant role in keeping stale, recirculated air clean. Plants create fresh oxygen, filter dangerous toxins out of the air, and add a bit of fresh air to any room they live in. For the most part, houseplants are pretty easy to care for, but the winter season can present some special challenges for them. Here are a few quick tips to make your indoor garden a successful one.

Adequate light is one of the most important environmental factors in successfully growing plants indoors. Too little light may make your plant leggy with spindly new growth. Let your plants receive as much light as possible during the darker winter days. As the angle of the sun changes and the days get shorter, you may want to rearrange your plants to ensure they’re getting sufficient light in the winter months.

If you don’t have a sunny windowsill to house your indoor garden, grow lights can be especially useful. The proper lighting can supplement sunlight, or replace it entirely in the winter! Echter’s carries everything from full-spectrum bulbs to fluorescent grow tubes that fit in standard fixtures. Add some digital timers, and getting enough hours of light for your houseplants becomes effortless!

Place your plants well away from winter’s chill. Don’t put them near entry doors where they will be exposed to cold drafts. Make sure the leaves of your plants living in window areas don’t actually touch the window. Minimize exposing plants to temperature extremes by placing them well away from your heating system’s air vents and also away from your fireplace.

Remember that indoor plants need less water & fertilizer during the short days of winter. Shorter days mean less growth, so you’ll want to water only when your plants require it.

Overwatering is the number one killer of houseplants! Frequent watering forces air from the soil and opens the door for root-killing bacteria and fungus to move in. Surface soil can dry out more quickly during winter months, but that’s not a good indicator that the plant needs water. Push your finger into the soil to determine if it is dry an inch or two below the surface—that’s when it’s time to bring out the watering can. Avoid shocking your plants’ roots by using room-temperature water in the winter. Use fertilizer at half strength every other time you water until about mid-March.

Houseplants will benefit from added humidity. Humidifiers are great, but you can also use a simple-to-make pebble tray. Take an oversized saucer, add pebbles, and fill halfway with water. Then place your plant on the pebbles. As the water evaporates, add more, but don’t let the plant sit in water. 

Dry air in our winter-warm homes can create a favorable environment for pests. Keep a close eye on your plants’ leaves for signs of problems. Periodically check your plants with a magnifying glass.

Thoroughly check the undersides of leaves, stems, and branch axils. Look for common plant pests such as spider mites, mealybugs, whiteflies, & fungus gnats. Spotting problems and responding to them early can keep populations from exploding.

Just as winter is a season of rest for the outdoor garden (and the gardener!), consider it an off season for your houseplants, and give them a season of rest too. Give them the essentials, but leave things like repotting and propagation until spring when your plants begin growing actively again. Next spring, after a long winter’s nap, your plants will be ready to get growing again!

Beat the Heat in the Summer Garden!

We’ve experienced some very warm weather this last week, and it looks like there is going to be more of it next week!  Some of your plants may be showing signs of heat stress. Leaves may wilt. Vegetables like lettuce and spinach may bolt (flower prematurely) or in the case of plants you want to blossom, like peppers or watermelon, they may drop blossoms, reducing yield. Here are a few tips to help your garden withstand the hottest part of the summer.

Watch Your Plants
Plants will often tell you when they are needing water. Lawns will turn a bluish green and show footprints that don’t rebound. Bean leaves will turn a darker green and begin to wilt. Most plants will perform better if you don’t allow them to wilt before watering, so check your garden every day and observe their needs.

Water When Necessary
It’s true that you need to water more often during hot weather, but first check the soil. The surface may look dry even though there is plenty of moisture in the root zone. Over-watering can be just as harmful as under-watering, so don’t over do it. Slow, deep watering will ensure that water soaks down to the roots. Soaker hoses and drip irrigation systems work well.  If using a hose that has been laying in the sun, be sure to let it run for a minute or two, until cool water comes out.

Mulch to Keep
Things Cool!
A couple of inches of organic mulch like compost, grass clippings, or bark mulch will help reduce moisture loss as well as cool the soil temperature. A side benefit is that it prevents most weeds from germinating, too!

Cover cool-weather veggies like lettuce and spinach with shade cloth. It won’t totally prevent bolting, but it might delay it a bit.  Also, raise your lawn mower blade up so that you have 3 inches of grass left standing after you mow.  This will provide shade for the roots of your lawn keeping them cool and much happier (which means a greener lawn).

Don’t Spray Chemicals
During Heat
Avoid spraying garden chemicals when temperatures are above 85 degrees. Weed killers can volatilize (evaporate and become air borne) and drift onto desirable plants. Insecticides can burn leaves of plants when temps are above 85. Spray early in the morning when temps are cooler and the air is still, or wait.

Summer is just getting started! With a little extra attention and a little extra know-how, your garden can come through this summer’s heat waves with flying colors, and keep right on blooming!