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Dahlia bloom season


When Do Dahlias Bloom? (Essential Guide)

There’s no doubt that dahlias are some of the stars of summer. With flowers that come in just about every shape and color imaginable, these blooms know how to brighten up a space. Not only are they gorgeous, but they’re also long-lasting and offer rich symbolic value and lots of added benefits! With the proper care, dahlias can flower for up to four months. Keep reading to learn more about when and how long dahlias bloom.

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The Dahlia Season Essentials:

Dahlias are warm-weather flowers that bloom mid-summer through fall. They begin to bloom a couple of months after the soil warms, and continue to bloom until early to mid-fall. Both the environment and variety can impact when and how long a dahlia will bloom.

Dahlia Basics

Dahlias are members of the Asteraceae family, along with daisies, sunflowers, and zinnias. However, unlike many of their family members, dahlias produce starchy tubers.

Rather than planting seeds, gardeners typically plant dahlia tubers. These tubers can produce flowers each year, as long as they do not succumb to cold temperatures.

Although all types of dahlias grow in a similar manner, you can find diversity in plant height, flower size, flower shape, and color (including the infamous black dahlia). There are 42 known dahlia species, but there are thousands of cultivars within these species!

Professionals break dahlias down into 12 different divisions:

  1. Anemone
  2. Ball
  3. Cactus
  4. Collarette
  5. Decorative
  6. Mignon
  7. Peony Flowering
  8. Pompon
  9. Semi-Cactus
  10. Single Flower
  11. Topmix
  12. Waterlily

While all of these divisions have variations in how their flowers look, they can all be treated similarly. Additionally, they will all bloom for a similar length of time.

Where are Dahlias Native To?

All 42 species of dahlias are native to mountainous regions in Mexico and Central America. Since these regions do not experience frost, dahlias grow as perennials.

When Are Dahlias in Season?

In most areas, dahlias are summer and early fall flowers. Since they cannot survive cold temperatures, growers must wait until the ground warms to about 60ºF in the spring before planting dahlia tubers.

Once gardeners plant the tubers, the flowers will begin to bloom in about ten to sixteen weeks. In many places, this means the dahlia season starts in July.

Most dahlias will continue to bloom until fall frost arrives. This means dahlias will continue to bloom until mid to late fall in many areas.

Even if you live in an area without frosts, dahlia blooms will still slow in the winter due to decreasing light.

How Long Does the Dahlia Season Last?

Dahlias will continue to bloom until they are killed by the first frost. Therefore, the length of the dahlia season depends on your climate. However, dahlia season lasts four to five months in many areas.

If you want to make dahlia season last a bit longer, you can try a few different techniques. Some of these will encourage dahlias to bloom earlier in the year, and others will extend fall blooms.

To get the dahlia season off to a quick start, you can plant tubers in a warm indoor area. This will give the plants a headstart while it is still cold outside By giving the tubers a chance to sprout and grow a bit indoors, they will bloom earlier in the year.

If you want to extend your dahlia season in the fall, you can utilize protective coverings. Frost cloth, low tunnels, and high tunnels can all be used to extend the season a bit longer.

However, since dahlias can grow four to five feet tall, covering them can take a bit of work.

Factors Influencing the Dahlia Season

Numerous factors impact the timing and length of dahlia season. These include the climate, dahlia variety, and when you plant dahlia tubers.

Climate

While dahlias are technically perennials, they are sensitive to cold. Therefore, gardeners in growing zones eight and below typically replant dahlias tubers each spring.

Since dahlia tubers aren’t cold-hardy, gardeners must wait until both the air and soil have warmed before they plant the tubers. If they plant the tubers too soon, they may become damaged or die.

A good rule of thumb is to wait until the last predicted frost date has passed before you plant your dahlia tubers outdoors. Additionally, you should wait until the soil has warmed to 60ºF.

Since the soil will warm later in the year in cooler areas, this means dahlias bloom later in the year in cooler regions. However, pre-sprouting dahlias indoors can help cooler regions catch up with warmer regions.

Additionally, a late frost can cause dahlia setbacks. Therefore, a warm spring will allow dahlias to bloom earlier than a cool spring.

Finally, cooler areas typically receive earlier frosts than warmer areas. Therefore, you can expect dahlias to bloom later into the season in warm areas.

Environment

If you’re not providing your dahlias with the proper sun, water, and soil, the plants will have a difficult time growing. And slow-growing plants mean blooms don’t appear until later in the season.

If you want your dahlia season to last as long as possible, follow these care guidelines.

Sun: Dahlias love sunlight, ensure they receive at least six hours of direct sun each day.

Soil: Choose loose and well-drained dahlia soil. Amend with compost if necessary.

Water: Aim to keep dahlia soil moist but not saturated through regular waterings. 

Fertilizer: Fertilize dahlias monthly with a slow-release fertilizer that’s high in potassium and phosphorus but low in nitrogen.

Additionally, you should make sure your plants have enough room to grow. Only plant dwarf varieties in dahlias, and provide adequate spacing between plants.

If you’ve planted your dahlias at the correct time but are not seeing any bloom after a few months, there’s a good chance improper care is to blame.

Pruning

While dahlias don’t need to be pruned, some growers opt to pinch or top their plants. This involves removing the terminal bud so the plant grows bushier.

If you pinch your plant, it will take a couple of weeks longer for it to flower. However, the plant will likely produce more flowers over the course of the season.

Dahlia Variety

While all varieties of dahlias are sensitive to cold, some will sprout and bloom quicker than others. In general, smaller flowers with fewer petals will bloom earlier than larger flowers.

With that said, you may notice a different variety blooms first each year.

Types of Early-Season Dahlias

If you’re looking for dahlias that bloom early in the year, you’ll generally want to look for small flowers. However, this is general guidance and not a rule. 

Types of Mid-Season Dahlias

As we mentioned above, it’s hard to say what variety of dahlia will bloom when. Factors such as temperature, water, and sunlight can all affect when a dahlia blooms.

With that said, these types of dahlias often bloom mid-season.

Types of Late-Season Dahlias

These varieties may bloom early in the year, but they are often some of the last dahlias to flower.

Wrapping Up

Although the dahlia season depends on the climate, care, and type of dahlia, you can expect to enjoy these flowers for multiple months. So choose a few varieties and get planting! For more, see our in-depth guide to growing dahlia flowers in your garden and cutting dahlia flowers for a vase or bouquet arrangement.

Briana Yablonski

Contributing Editor | Full Bio | + posts

Briana holds a B.S. in Plant Sciences from Penn State University. She manages a small market garden where she grows vegetables and herbs. She also enjoys growing flowers and houseplants at home.

How Long Do Dahlias Take to Bloom? | Home Guides

By SF Gate Contributor Updated June 08, 2020

With blooms between 2 and 10 inches wide, dahlias produce flowers in almost every color imaginable, from yellow to lavender, including some with bicolor blooms. The intricate blossoms decorate your garden during the summer and into the fall when many other plant blossoms are dying back.

The Missouri Botanical Garden lists dahlias Preferring the temperatures in U.S. Department of Agriculture plant hardiness zones 7 through 10, dahlias need some mild temperatures, proper planting and strategic pruning to encourage healthy and long-lived flowers.

Tip

From planting dahlia tubers to seeing the plants flower generally takes around eight weeks.

Soil Temperature Influences Dahlia Growth

If you plant your dahlias in the early spring, the cold soil hinders initial growth -- your soil needs to be warmer than 62 degrees Fahrenheit for dahlia tubers to sprout. Because of the initial slow growth, you need to avoid watering dahlia tubers until sprouts are visible above the soil surface.

To encourage faster sprouting and blossoming, use a soil thermometer to gauge the best temperature. Late spring plantings respond better to the surrounding temperatures and produce sprouts and flowers quickly.

Tubers store the necessary dahlia nutrients for prolific blossoms, but wet soil contributes to rot and failed sprouting. If you live in a particularly wet climate, growing dahlias in pots offers sharp drainage, which helps to keep the tubers from becoming waterlogged. And when you see dahlias for sale, inspect the tubers to make sure they are firm and not mushy but also that they're not dried out.

Dahlias: When Do They Flower?

The Old Farmer's Almanac notes that eight weeks generally need to pass between planting and blossoming for most dahlia varieties. For example, your tubers planted in April should form flowers by June. However, most dahlias bloom in July as they respond to the warm temperatures; they also last until September or October.

With a full sunlight location in nutrient-rich and well-drained soil, your dahlias blossom on time if they are correctly oriented in the soil at a 6- to 8-inch depth. The bud points across the tuber need to face the sky for sprout access to the sunlight. Additionally, inspect your growing dahlia for flower buds daily -- you should pinch the first buds off of the plant to encourage larger buds to form afterward.

To Keep Dahlias Blooming

With a blossoming season that can last as long as 4 months, your dahlias easily re-flower with consistent deadheading. The Missouri Botanical Garden recommends cutting off the spent blossoms to encourage the plant to create new flowers. This is a natural plant response because it wants as much reproductive success as possible -- removed flowers means it needs to create more for pollination and seeding.

If your dahlia is a relatively tall cultivar, keep it wind-protected to prevent damage. Dahlias that have torn or broken limbs may not have the energy for continual summer flowering.

Detrimental Growing Conditions

If you dahlias are subjected to drought conditions coupled with hot temperatures, your blooming period may be shorter than normal. To combat environmental stresses, strategically plant your tubers in a location that receives full morning sunlight with some dappled shade in the afternoon.

The initial sprouting to blossom time should still remain around 8 weeks with some sunlight shelter. Extreme summer heat is also reduced during the flowering period with some shade for long-term blossoming into the fall.

References

when to plant in spring, how to prolong flowering

There are many ornamental varieties of dahlias that differ in leaf shape, flower shades, stem length. If you are interested in the question of when dahlias bloom, you need to study the information about the selected plant species and the characteristics of its flowering. The period of appearance of inflorescences also depends on the time of planting, growing conditions, proper care and timely feeding.

Contents

Dahlia flowering time

Early varieties of dahlias begin to bloom 30-40 days after planting, later varieties - after 70-80 days. Most species of this plant bloom in June. The flowering period lasts until the first frost and ends in September-October. Subject to the storage conditions of dahlia tubers in winter and good weather conditions in spring, earlier flowering can be achieved, starting at the end of May.

When to plant dahlias in the spring

Dahlias do not tolerate frosty weather, during short frosts the tubers can rot and die. Therefore, the timing of planting a plant in open ground depends on weather conditions.

When to plant in the spring according to the lunar calendar 2018

According to the lunar calendar of the gardener and gardener, it is desirable to plant flower plants during the growing moon. This is due to the fact that in the growth phase, the satellite attracts all the water on the planet, including the juice in plant cells. In 2018, in the spring, dahlias can be planted on the following dates: May 4-6, 14, 16-24, May 26-28. Astrologers recommend planting later varieties on June 6-7, 10-11, 15-20, 22-25 June.

According to the lunar calendar 2018, the unfavorable days for planting this plant in open ground are 15 and 29May, 13 and 14 June.

If the weather deteriorates on favorable days according to the lunar calendar, it is necessary to reschedule the procedure to another time, while avoiding full moon and new moon days and the dates closest to them.

When to plant

Traditionally, the roots of this flower are planted in the soil in mid or late May, when the ground has warmed up enough. In addition, during this period, most often there are no sharp changes in the weather, cold rains and gusty winds. The day for planting must be chosen warm and sunny.

In regions with a more favorable climate, dahlias can be planted outdoors in March-April. At the same time, it is necessary to carefully monitor the weather forecasts and, in case of threats of frost, provide the plants with a thorough shelter. At the same time, tubers germinated in advance at home should be transplanted.

Late varieties should be transferred to the soil at the beginning of summer, when the air warms up well and the weather is warm.

How to make dahlias bloom as early as possible

In order for the flowering period of bushes to come as quickly as possible, a month before planting in open ground, it is necessary to germinate tubers, thereby preparing the plant for favorable and productive cultivation. To do this, in April, root crops should be sprinkled with moistened coconut substrate, peat or sawdust and sand, and then placed in a warm place: a greenhouse, a greenhouse or on a windowsill. The emerging sprouts can be dived into separate containers, while providing them with timely watering and additional care.

After 3-4 weeks, tubers with young sprouts should be transferred to a permanent place. In open ground, when planting dahlias, add special fertilizers. As the leaves appear, pinch the shoots. It is necessary to pinch the top of the stem above the third or fourth leaf. Carry out this procedure with secateurs and disinfect the instrument after each removal. If these recommendations are followed, dahlias will bloom much earlier than the due date.

How to get large flowers

In order to obtain large flowers and powerful stems, it is necessary to form a bush correctly and remove side shoots that appear in the leaf axils in time. This is due to the fact that the extra shoots take a lot of nutrients and do not allow the flowers to develop. Therefore, pinching plants of medium and tall varieties is a mandatory procedure for obtaining large buds.

Professional flower growers advise leaving 2-3 shoots on the tuber and cutting off excess stems throughout the season. In addition, it is necessary to remove the leaves at the bottom of the bush and cut off the wilted flowers. This will provide access to light, heat and air to the soil and will stimulate the rapid growth of the plant.

To obtain large flowers when planting dahlias in open ground, provide them with fertile soil and spacious garden areas that receive sunlight. A large feeding area will improve the flowering quality of the plant.

Ornamental dahlias are highly susceptible to various diseases and insect attacks. In order for young buds to remain strong, and subsequently large voluminous flowers appear, it is necessary to regularly treat the bushes with special pest control agents, for example, solutions of celandine or wormwood, soapy water or systemic insecticides.

In addition, dahlias need proper moderate watering, timely fertilization with phosphorus and potassium, loosening the soil, cutting dried leaves and removing faded inflorescences. Such comprehensive measures will allow the flowers to develop and reach large sizes.

How to prolong the flowering of dahlias

Dahlia species, which bloom for quite a long time, do not need additional care and can delight with their flowers for a long time. To increase the flowering period in annual plant varieties, you should regularly inspect the bushes and pluck drooping and dried heads. This method of care will prevent the depletion of the plant and will stimulate the formation of new buds.

Dahlias need to be properly fertilized in order to produce abundant and long-lasting blooms. The last top dressing is best done no later than the end of July. In this case, the bushes will not actively grow greenery, and the flowers will receive more nutrients and remain lush and beautiful longer.

At the end of August or beginning of September hilling should be carried out, forming a small mound of earth around each plant. In this way, tubers can be protected from a strong difference in day and night temperatures and the first autumn frosts.

In addition, in case of worsening weather conditions and the threat of short-term sub-zero air temperatures, carefully cover the bushes with light materials: polyethylene, geotextile or burlap. When warm weather sets in, the protective coating must be removed and the stems of dahlias should be carefully straightened.

When dahlias bloom

Contents

Dahlia got its proud name in honor of the Russian traveler, ethnographer and naturalist of German origin Johann Georgi. In foreign literature, the flower is known under the name "Dahlia" (Dahlia). The dahlia is native to South America. The ancient Aztecs saw in it the earthly incarnation of the sun and used it in solar cults. In modern Mexico, the flower has acquired the status of a national symbol. From the end of the 18th century, the plant became widespread in the Old World and more than once caused a fashionable boom, becoming the most popular and sought-after flower, especially among the nobility.

Dahlia belongs to the Asteraceae family, has 42 species and an unimaginable variety (about 15 thousand) of varieties. Under natural conditions, a wild-growing dahlia can reach six meters in height. Garden cultivars of this plant are much lower - usually do not exceed one and a half meters.

Dahlia flowers can be either simple or double, sometimes spherical. In some garden species, “echoes” of wild American progenitors have been preserved, the baskets of which were composed of two forms of flowers: reed (external, not producing offspring) and tubular (internal, fruitful). Shades of dahlias are incalculable. Flowers are monochrome and variegated.

The great advantage of these plants is their rather long flowering. In the middle lane, it begins approximately in mid-late June and ends with the onset of frost. Due to the long flowering period, which lasts almost until winter, dahlia was nicknamed the “queen of autumn flower beds” - after all, at the time when dahlias bloom, most of the garden crops die off or go into winter “sleep” mode.

What should I do to make dahlias bloom as soon as possible?

To enjoy the flowering of dahlia already at the beginning of summer, the tubers must be prepared for planting in advance. Around April, they are added dropwise to moist, organic-poor soil (sand, coconut fiber, peat-based soil mixture) and placed for distillation in a greenhouse, greenhouse, or simply on a windowsill in a room. In May, the rhizomes with green sprouts that have appeared are planted under the open sky in a permanent place. With this approach, dahlias bloom a month after planting, while in the absence of preliminary forcing, the first flowers are observed no earlier than the end of July. To avoid an unwanted shift in dahlia flowering, they also try not to be late with pinching. They are produced after the appearance of four pairs of leaves in the distance. Dwarf, border varieties of dahlia and plants grown as annuals do not need pinching.

How to get large flowers?

The fewer flower buds on the plant, the larger they are, since all the nutrients will be directed to a few flowers, and not dispersed over a multitude. This rule also applies to dahlias. It is recommended to leave two or three main stems in the distance, on which buds will subsequently appear. All the rest are removed in their infancy. In addition, it has been noticed that large flowers grow on bushes expelled from young divisions. Therefore, you should carefully consider the planting material and discard old tubers in advance.

Why do dahlias bloom poorly?

There may be several reasons. Let's mention the main ones.

  1. Often, gardeners, in pursuit of the splendor of the bush, overfeed the plants with fertilizers, primarily nitrogen. And, as you know, this element causes the culture to intensively increase leaf mass. The process of ripening flower buds slows down. During the period of dahlia budding, the nitrogen content in complex fertilizers should be minimized, and if there is an excess of a substance in the soil, it should be completely abandoned.
  1. Dahlias are natives of tropical and subtropical latitudes. In the wild, they are found on the sun-drenched hillsides of Mexico, Chile and Peru - regions in which the number of sunny days per year sometimes reaches three hundred. It is quite natural that good lighting is one of the important conditions for the normal development of these plants. For planting dalia, it is recommended to choose open garden plots. The lack of sunlight leads to the crushing of peduncles and a decrease in pigment in the petals, dahlias bloom later, and sometimes do not form buds at all.
  1. When cultivating a plant with tubers, many gardeners make the mistake of planting a bunch of tied rhizomes left after harvesting a dahlia the previous autumn in one bush, believing that the more massive the root, the more magnificent the flowering will be.

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