Flowers

Dahlia Guide: How to Grow & Care for These Beautiful Flowers

Our Guide to Dahlias - Everything you will ever need to know! Tips for growing and caring for these flowers

If you are here, then you must be ready to add another beautiful member to your plant family. The truth is that Dahlias are one of a kind and truly deserve a place in every garden. Growing them has many advantages and no disadvantages at all, which is why we always recommend people to grow them.

Dahlia is an interesting genus that contains exactly 42 species of bushy flowering plants in the Asteraceae family. Why interesting? Well, these plants come along with spectacular blossoms. Their flowers can come in a wide range of shapes and mesmerizing color mixes that will enchant any gardener out there. And once you see how special these flowers can be, their low-maintenance style will only be a well-received bonus.

About Dahlia Plants

  • Although these flowering plants are native to Mexico, some species grow natively all over northern South America.
  • Thanks to their stunning flowers, about 124 Dahlia cultivars have gained the prestigious Award of Garden Merit from the Royal Horticultural Society.
  • The largest flower parade worldwide called Bloemencorso Zundert. For this parade volunteers use Dahlias to decorate objects and to create mixed-media artworks with steel wire, paper-mâché, and cardboard.
  • Dahlias are still considered one of the main ingredients in Oaxacan cuisine. Oaxacans grow certain Dahlia cultivars for their large, edible, and tubers that resemble sweet potatoes.
  • An extract from roasted Dahlia tubers ‘Dacopa’ is quite popular and people use it to flavor various beverages in Central America. It is intense and has a taste that resembles mocha.
  • Dahlias grow at their best when they get full sunlight and at slightly warmer temperatures. They thrive in well-draining soil and are pretty drought-tolerant.
  • They appreciate humidity only when you store them as tubers. During their growth period, from spring to summer, these plants do well without additional humidity.
  • Although you can grow Dahlia plants safely around children, they can be mildly toxic to curious cats and dogs if ingested.
Dahlia Flowers
Dahlia Flowers

Dahlia Plants Features: An Overview

  • The flowering plants of the Dahlia genus grow natively in the uplands and mountains. They grow at higher elevations between 4921 and 12139 feet (1500-3700 m).
  • Dahlias are herbaceous and perennial plants that can reach from 1 to 8 feet (0.3-2.4 m) in height and 1 to 3 feet (0.3-0.9 m) in width. Gardeners grow these flowers as annuals in regions with harsh winters.
  • These plants are borne from tubers (tuberous roots) and specialists classify them according to petal arrangements and flower shapes. Their overall growth is somewhat bushy.
  • The 14 groups of Dahlias are Single-flowered, Anemone-flowered, Collerette, Waterlily, Decorative, Ball, Pompon, Cactus or Semi-cactus, Miscellaneous, Fimbriated, Double or Single Orchid (Star), and Peony-flowered.
  • Their foliage consists of many blue-green to purple-burgundy leaves that grow on long stems of 12 inches (30 cm) to 8 feet (2.4 m). The leaves are broadly ovate, matte to glossy, and usually have serrated margins.
  • During their blooming period, from summer to fall, Dahlias produce lovely flowers that come in a wide range of colors excepting blue. Some species have blossoms that appear in hypnotic mixes like white-purple, yellow-red, or creamy-pink.
  • They make for great companions to other perennial species of plants, such as Agastache ‘Black Adder’, Aster amellus ‘King George’, Echinacea purpurea, Echinopsis, Geranium, Sage, Stonecrop, Lily, Kniphofia, and Monarda.

Growing Dahlia Plants

With time, you will be more than pleased to find out that Dahlia plants are fairly easy-going to have around, especially if you grow them indoors. Although they are not the hardiest of plants, you can move Dahlias indoors during the winter and store them in a dry, cooler, and frost-free location. Then, when the spring comes along with a little warmth, you can bring them back outdoors and transplant them back into to the ground.

To ensure that they will bloom well and produce many flowers, you must grow your Dahlias in a location where they can receive at least six to eight hours of bright and direct light daily. They are lovers of full sunlight but will grow better in partial shade if you live in a region with hot and dry climates. The afternoon sunlight can burn and damage them irreversibly, so you need to protect your beauties during these extreme and hot times.

Dahlia Flower Seeds, From Amazon

Temperature-wise, Dahlia plants will grow at their best in slightly warmer conditions. The ideal temperatures for these flowers range from 68 to 72 °F (20-22 °C) during the day with a minimum of 60 °F (16 °C) at night. Higher temperatures will accelerate blooming, but might also affect the quality of your plants if they need to adapt to drought for longer periods.

Pests like slugs, earwigs, thrips, or caterpillars can disturb your beautiful Dahlias, but there are many effective solutions to these problems. If you notice any suspect presence on your plants or signs of infestations, you should treat them with suitable insecticides or pesticides right away. Dahlia plants are also prone to fungal diseases including powdery mildew. You can treat the infected parts with neem oil or other natural substances.

Planting Dahlias

When it comes to planting and growing Dahlia plants, timing plays a big part. These plants will struggle to settle in cold soil, so you have to wait until the final frost has passed in spring. If you want to make sure you are doing a perfect job, you can check the ground temperature before planting. The outdoor soil’s temperature should be around 60 °F (16 °C), but you can also start your tubers indoors earlier in containers.

The growing medium in which you want to plant your Dahlias is probably the most important factor for thriving plants. These flowers prefer rich, well-draining, and neutral to acidic soils with an average pH of 6.5. They are lovers of organic matter and will not hesitate to show their gratitude when provided with plenty of nutrients.

If you are starting your Dahlias ahead of time in pots, it is best to combine the commercial potting mix with some garden soil. Typically, potting soils tend to dry out pretty quickly and Dahlia tubers enjoy having moist feet until growing enough roots.

From spring to August, Dahlia plants will benefit greatly from regular feedings with a fertilizer that is low in nitrogen. As a general rule, the more fertilizer these flowering plants get, the larger and stronger roots they will develop. And we, gardeners, know that healthy plants will exhibit even more and bigger blossoms for us!

Dahlia
Dahlia

Watering Dahlia Plants

Unlike many other species of flowering plants, Dahlias (especially young specimens) will do just fine without too much water. These drought-tolerant plants are an excellent choice for beginners or forgetful gardeners, but make sure you do not over-water them! They are susceptible to root rot, so it is always better to provide your Dahlias with water only when needed.

Because Dahlia plants usually have their roots pretty close to the surface of the soil, they can thrive with typical summer rainfalls. However, if you live in a region with seldom to no rainfalls, supplemental irrigation or watering may be necessary.

In general, Dahlias require at least one inch (2.5 cm) of water weekly to grow healthy and happy. During their watering routine, it is very important to never allow the soil to dry out. If Dahlias have their feet dry for a long period, this will eventually result in dry or even dead plants.

Propagating Dahlia Plants

Sometimes, Dahlias do not have a chance to show off their perennial features and require a little extra help to make it through the next growing season. Although this thought might seem scary for beginner gardeners, you should not worry too much about it. No matter how experienced you are in the gardening world, we’re sure that you can succeed. Once you master the art of producing baby Dahlias, you can put your friendly plants into the spotlight and surprise your family members or friends with a stunning gift!

Luckily, you can propagate Dahlias from seeds, cuttings, or tubers. The main use of propagation through seeds is developing new cultivars, as seeds can only produce varieties that are different from the mother plant. The propagation method using tubers is the most common among Dahlia growers because it will result in a clone of the parent plant. However, if you want a fun challenge, cuttings are the best alternative to increase the stock of your favorite Dahlias.

Pink Dahlia
Pink Dahlia

Propagation through stem cuttings is a quick and easy process because we are using young shoots that grow very fast. Look for healthy shoots that have three to four pairs of leaves and take cuttings just above the lowest nodes or joints using a sharp, sterilized knife. Remove the lower leaves, making sure to let two leaves intact at the top. For optimal results, dip the bottom of the cuttings in rooting hormone before planting.

Place your Dahlia cuttings in a pot that you’ve filled with equal parts of potting mix and sand. After planting, you must keep the cuttings in a warm room and provide them with enough water to maintain the soil damp. With proper care, your cuttings will develop new roots in two or three weeks and then you can transplant them in the garden or into individual pots.

In Conclusion

Many gardeners consider Dahlias very picky and hard to please, but this could not be farther from the truth! As long as you provide them with suitable environmental conditions, rich and well-draining soil, and regular watering and fertilizing, everything will go as planned. We can assure you that Dahlias will be the perfect companions for you during the summer months. And with their easy-to-propagate nature, you can have these hypnotizing beauties around for as long as you want!

Are you growing Dahlias? Share your experience in the comments below!

Miruna is an experienced content writer with a passion for gardening. She is the proud owner of an outdoor rose garden and an indoor collection of tiny succulents. She bought her first succulent 10 years ago - an adorable Echeveria Setosa. Now she owns more than 100 succulents and cacti of different colors, shapes, and sizes. Miruna is a versatile writer and, as you might have guessed, her favorite topic is gardening. Contact miruna@gardenbeast.com

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