Dahlia Sun Or Shade – Which One Is Best

Dahlia Sun Or Shade – Which One Is Best?

Gardeners who want to know what conditions are best for growing this striking flower have asked dahlia sun or shade questions so many times.

With their striking, sculptural, beautiful flowers, dahlias bring a sentimental touch to your garden and home.  They are so prevalent in floral arrangements; it’s no surprise that many dahlia enthusiasts seek to maximize on these blooms like no other.

A common question is how much sun or shade should you give these flowers.  So are dahlias sun plants or shade plants?

The Perfect Dahlia Sun Or Shade?

Will dahlias thrive under the sun? Yes. Will dahlia thrive under the shade? Yes. So what’s the big deal?

Dahlia flowers are best grown in locations that receive over 6 hours of sunlight and can remain moist, not dry out or wilt.  Too much sun can give rise to the dryness of your dahlia plants.  So when it comes to growing a perfect dahlia, shade is part of its growth system.

The Perfect Dahlia Sun Or Shade

Can Dahlias Grow In The Shade?

Dahlias are used to bright sunlight and warm weather, and most of them will do well in full sun.  However, some varieties evolved as forest edge plants and only need a few hours of direct sunlight each day.  Said, some types will be better in the shade than others.

If you buy Dahlias from a specialist grower, they will probably know which ones grow better in shade or sun.  Ensure that you ask this question before you purchase any dahlia plant.

Dahlias Like It Warm, Not Too Hot

So how much sun for dahlias?  Like most flowers, dahlias have been grown for a longer time.  These flowers are native to the mountains of Southern Mexico and Central America, where summer days are warm up to 80 degrees F and nights are cool with 65 degrees F.

The growth conditions along the Pacific Northwest Coast are similar, which is why gardeners who live around that area grow such beautiful dahlias.

If temperatures get warmer during the day or night, dahlias may show signs of stress.  Heat or cold stress causes these flowers to get stunted growth, poor flower production, misshapen flowers, and increased susceptibility to pests and diseases.

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So Is The Full Sun Always The Best?

There is no doubt dahlias are sun lovers, and more sun for any flower farmer means more bloom.  However, if the sun is too hot and the temperatures are too high, the plants may stop flowering.

Choose a planting location that offers half sun and half shade instead of the full-day sun to protect your dahlias from excess heat.   Ideally, your plants will get full morning sun and shade in the afternoon.  You can also plant these flowers beneath a shade tree.  The overheard branches will protect the foliage from the afternoon’s hot sun and reduce the air temperature.

Read more about Zinnias Sun Or Shade – What Is The Best?

What If You Don’t Have Shade Where You Are Growing Dahlias?

If you have no shade where you are growing your dahlias and live in a hot climate, consider putting up a shade structure. It’s an ideal solution for gardens that do not have any shady areas.

To make your shade, use a polyethylene shade cloth that lasts for many years.  Depending on the weave, you can filter out as little as 20% of the light or as much as 80%.  If you give dahlias 40% of light, they will still thrive.  This fabric also shields the flowers from the heavy rain and hail that could be damaging.

How Else Can You Cool Your Plants?

In case you are experiencing too much sun, it’s best to cool off your plants by mulching.  Covering the soil with mulch will insulate the roots of these plants and help protect them from extreme heat.

Ensure that your mulch is no more than 2 or 3 inches thick, and it must allow water to flow through it to the soil.  The best time to apply your mulch is early June when your plants grow strong and before it gets too hot.

Dahlia Sun Or Shade – The Right Balance

Most plants require the sun and water to thrive; however, the optimal amount of each depends on the individual plant.  Many plants can flourish and do well in less than ideal conditions.

Even in these adaptable situations, flowering can be given a better positioning by the natural environment. Ensure for any plant you plant in the shade; you assess the amount of sun it will get and vice versa.

Soil, Organic Matter, And Proper Drainage

Besides the sun or shade needs, provide dahlias with plenty of organic matter and proper drainage. Dahlias prefer rich soil.  Before you plant them, enrich your soil with a generous amount of compost, old manure, or shredded leaves.  Loose soil that has been enriched with organic matter encourages strong root growth and absorbs moisture properly.

Plant your dahlias in well-draining soils to prevent your plants from being soggy and dying from too much water. Wet roots stress the plants causing the tubers to rot and the plants to die. If you notice your soil is naturally heavy, consider growing your dahlias in raised beds.  This way, you can fill the beds with the best possible soil and ensure proper drainage always.  Also, consider increasing dahlias in containers and fill them with a professional high-quality growing mix that has been amended with compost.

Soil, Organic Matter, And Proper Drainage

Watering Dahlias

Dahlias don’t like too much water, but drought can cause them to dry up and die.  If natural rainfall fails or is inadequate, it’s best to water your dahlias deeply once a week rather than water them lightly several times per week.

The best watering method uses drip irrigation to keep the foliage dry and water the plants down to the roots with no runoffs.  If you are hand watering, pour the water directly at the soil level to avoid getting the leaves and flowers wet to discourage mildew and mold growth.


Dahlias are beautiful flowers to grow with low maintenance and growing requirements.  Growing them under balanced sun or shade will result in a good harvest of these beauties.