Light: Full sun is ideal for zinnia growth and flowering. Even in warmer climates with afternoon shadow, they can flower there, but they may be more prone to disease and produce fewer flowers.
Soil: Organically rich, fertile soils with good drainage are ideal for growing zinnias. Because zinnia seedlings are susceptible to rotting in cool, damp soils, having well-drained soil is crucial.
Plant zinnia seeds in rows or clusters spaced a few inches apart. Once the plant has four leaves, thin to 8 to 18 inches apart, depending on the variety.
Planting: Plant zinnias in the spring, just about the time you plant tomatoes, when all threat of frost has passed. Growing zinnias from seeds straight in the garden is simple. Start seeds inside four to six weeks before to your last frost date for earlier flowering.
How much cold can zinnias stand?
One of the simplest flowers to plant, zinnias grow quickly and provide a lot of blooms. Additionally, they will continue to bloom right up until the first fall hard frost. Consider trying zinnia flowers this year to add a huge splash of colour to your yard.
About Zinnias
Since zinnias are annuals, they will only produce blooms and seeds for one season before dying. The original plant will not reappear the following year. They are excellent for use as a cutting flower or as food for butterflies since they have vivid, solitary, daisy-like flowerheads on a single, tall stem.
Types of Zinnias
Zinnia elegans, the most widely grown zinnia species, has been developed to produce a large number of distinctive variants.
Single, semidouble, or double zinnia blooms are the three most common varieties. The number of petal rows and whether or not the flower’s centre is visible serve to distinguish between these forms:
- A single row of petals and the centre are both visible on single-flowered zinnias.
- Petal rows abound on double-flowered zinnias, and their centres are hidden.
- Between the two are semidouble-flowered zinnias, which have several rows of petals but discernible cores.
In addition to these shapes, zinnia flowers also occur in “beehive,” “button,” and “cactus” forms. Additionally, the plants themselves come in various heights: taller types function best as a garden bed’s background, while shorter varieties are useful as a border. There is a zinnia for every garden, in fact!
In an annual or mixed border garden, plant zinnias. Smaller zinnias work well as window boxes, edging, or in other containers.
To have a lot of flowers all season long, choose a place that receives full sun (6 to 8 hours of sunlight every day). Additionally, later in the season, foliar diseases like powdery mildew can be avoided by planting in an area with sufficient air circulation.
Although zinnias can grow in a variety of soil types, they prefer organically rich, well-draining soil. The optimal pH range for soil is between 5.5 and 7.5. The blooms will grow more quickly if compost (humus) is added to the soil. Find out more about soil improvements and getting the soil ready for planting.
When to Plant Zinnias
- Because they dislike being transplanted, it is advised that you start your zinnia plants from seed directly in the garden bed. From seed, they will develop quite quickly in the correct conditions.
- It should be noted that zinnias can be grown from seed inside if you like. Just make sure to transfer them gently and young.
- Because zinnias are delicate to frost, wait to plant them until after the last frost in your area. See the frost dates in your area.
- Zinnias can tolerate daily temperatures as low as 60F (16C), although a range of 7484F (2328C) is ideal.
- To prolong the flowering time, sow a new crop of seeds every week or so for a few weeks.
How to Plant Zinnias
- Depending on the kind, place plants 4 to 24 inches apart. (Many common kinds are planted 2 feet between rows and 6 inches apart within the row.) For information about each variety, consult the seed packet’s back.
- Plant zinnia seeds no deeper than 1/4 inch.
- The majority of zinnia cultivars will produce seedlings in just 4 to 7 days, but it may take up to two months or more for blooms to appear (depending on planting site and climate).
- To promote air circulation, thin seedlings when they are three inches tall, spacing them 6 to 18 inches apart. As a result, powdery mildew is less likely to grow.
- To promote development and blossoms, keep the soil’s moisture level moderate and apply a mild fertiliser.
- Deadhead zinnias once they have finished blooming to facilitate the development of new blossoms.
- Since zinnias are annuals, they will perish with the first fall hard cold. Let the final blooms of the season fully mature before dispersing their seeds if you want them to reseed.
Zinnias still not your thing? In your garden, try them out for the following six reasons:
- With cultivars from the Dreamland Series, you can have a full-sized flower on a little plant. These zinnias are compact and dwarf, with stems that are 812 inches tall and totally double flowerheads that can be up to 4 inches across with a variety of colours.
- The dwarf, spreading cultivars of the Thumbelina Series have weather-resistant, solitary or semi-double flowerheads in a variety of hues. Their stems can reach a length of 6 inches, and their petals are 1-1/4″ wide.
- One of the largest and tallest of them all, the State Fair Series has huge, double flowerheads that measure 3 inches in diameter. Stems can reach a height of 30 inches.
- Typically, it takes zinnias 60 to 70 days from seed to flower (though it depends on conditions and variety). They are fantastic in a bunch of flowers!
- The tiny, narrow-leafed zinnias are great for hanging baskets and also make lovely dried flowers.
- Zinnias are considered to represent memories of those who have passed away. Discover more about the significance of flowers here.
- Zinnias may be harmed by bacterial wilt, powdery mildew, and bacterial and fungal spots. To prevent illness, keep leaves from getting too damp and correctly space your plants.
- Problems can also be brought on by caterpillars, mealybugs, and spider mites. Spraying should be avoided unless there is a real infestation because some leaf damage is not a problem.
- Thanks to their resistance to deer, zinnias may be able to prevent surrounding flowers from being eaten.
When may I transplant my zinnia seedlings outdoors?
It is preferable to begin them at 4-6 weeks as opposed to 6-8 weeks. Make sure to transplant zinnias after the spring frost risk because they are not frost hardy. After your spring frost date, plant out 2-3 weeks later.
Can zinnias be sown right away?
One of my favourite garden tasks is caring for a cutting garden that produces fresh flowers all year long. Most people are unaware that zinnias may be planted into the late summer and enjoyed until the fall, despite the fact that they are a popular addition to spring cutting gardens. Zinnias grow well in hot climates and are simple to grow from seed. Because the temperature is typically a little dryer in the fall, zinnia growing conditions are ideal. I advise sowing zinnia seeds by August 15th to enjoy them all fall long. After the first frost, they will go extinct.
Full sun and well-drained soil are prefered by zinnias. Sow seeds 9–12 inches apart. Pinching zinnias when they are young is beneficial when they are grown for cut flowers. Longer flower stems and branching are encouraged by pinching. When the second or third true leaf set occurs, pinch off the new growth. Only one pinch is necessary. Additionally, zinnia cuttings encourage additional branching and flowering. I advise deadheading the spent flowers if you’d rather leave them on the plant. Deadheading is the process of removing wilted flowers to promote new growth and prevent disease.
Although zinnias can withstand short periods of drought, they occasionally need irrigation. Keep overhead irrigation to a minimum. Use a drip tape, a soaker hose, or just let your hose drip at the plants’ bases. The spread of illness can be stopped by watering the plants at their bases. Those who have ever raised zinnias are likely to have encountered zinnia leaf spots. Leaf spots on zinnias begin at the plant’s base and progress up the leaves, finally killing the plants. Different fungus diseases can cause zinnia leaf spots, which can be treated with fungicide sprays. Since you will have plenty of time to enjoy zinnias before the spots take over, I often advise against spraying them. However, if you must, consider rotating mancozeb with myclobutanil (Spectracide Immunox) every seven days to ward off the spots.
Although there are numerous zinnia seed variations available online, I find that whichever variety the neighbourhood garden centre provides works just as well. I suggest giving them all a try! Old favourites include The Benary Giant, State Fair, and Cactus Flowered Mix. Good fortune!
Do zinnias thrive in containers?
Zinnias provide colour to any flower garden, are excellent for cutting, are simple to cultivate from seeds, and are a terrific option for container gardening.
How cold can zinnia seedlings tolerate?
Zinnia should be planted in the spring, starting indoors if it’s too chilly outside, whether in a flower bed in your garden, a container, or a garden box.
Sowing zinnia
If temperatures have not yet above 65F, the zinnia flower must be planted in a protected area due to its fear of the cold (18C).
- In a glasshouse where the temperature is at least 60F, sowing takes place in March (15C).
- Starting in the month of May, seeds can be planted directly in the ground.
- Starting in May, plant your seedlings in the ground, leaving 8 to 12 inches (20 to 30 cm) between each plant.
You are completely able to gather Zinnia seeds from withered blooms and keep them dry over the winter in a paper envelope. In this manner, you can plant them the next year.
Planting zinnia
Wait until mid-May to plant your zinnia plants after you have prepared your seedlings in nursery pots or if you ever bought ready-grown plants in a horticulture store.
- The warmest area of your garden belongs to zinnias because they enjoy the sun.
- Combine special flower plant soil with garden dirt.
- Depending on the kind, place each zinnia 8 to 12 inches (20 to 40 cm) apart.
- ample water.
What occurs if zinnias are planted too closely together?
Annual herbaceous plants are those belonging to the genus Zinnia. This implies that they generate non-woody growth (for the most part). Within a single year or season of growth, they will blossom and produce seeds. They favour soil that drains properly and full sun (6 to 8 hours of direct sunlight daily).
With the exception of blue, zinnias bloom in a wide range of vibrant, cheery hues. Depending on the cultivar, flowers can range in size from an inch in diameter to five inches. There are zinnia variations that are single-petaled (with only one row of petals), double-petaled variants, and multi-petaled varieties.
Their blossom is essentially a composite flower because they are Asteraceae members. This indicates that what you perceive to be a flower head is actually a collection of little blossoms. The “petals are known as ray flowers, while the flower’s centre is covered in disc flowers.
Infections including powdery mildew and leaf spot diseases can affect zinnias. Making ensuring that any dew or moisture on the leaf surface can swiftly dry is crucial. More space between your zinnia plants will aid in enhancing the flow of natural air through the flowerbed. As zinnias wilt, they typically become brown before passing away entirely.
Watering the plant from below as opposed to above can assist keep the foliage’s surface dry. The foliage will dry off more quickly in the morning from the dew that will accumulate on the leaves at night if you plant in full light.
Do zinnias return each year?
As annual plants, zinnias do not return year after year. In other words, the flowers go through their full life cycle in a single year.
Because they succumb to frosts so quickly, zinnias are extremely susceptible to them. You must either resow every year or allow some of the zinnia blooms to naturally wither and drop to the ground so that the seeds will naturally germinate in order to have flowers in your garden every year.
To gather and store flower seed for springtime planting:
- Allow the blossoms to wither.
- Cut the blossoms off.
- Shake and massage the seeds carefully while holding a bag below.
- Save in seed packets with labels for planting the next spring or summer.
It’s not too difficult to cultivate zinnias because of how simple and low-maintenance they are, especially considering the reward of the lovely blooms that appear in the late summer.
Where is the Best Place to Plant Zinnias?
Zinnias grow best in well-drained soil that is rich in organic matter, whether they are grown in raised garden beds, pots, or directly in the ground.
Should You Pinch Zinnia Plants?
Pinching the young plants is the key to creating the best zinnias with the longest stalks. When plants are between 8 and 12 inches tall, cut off the top of the plant, just above a pair of leaves, with a pair of sharp garden pruners.
Should You Deadhead Zinnias?
Deadhead zinnias to prevent fading. Either remove the old blooms once they have faded or cut mature stems to utilise in fresh bouquets for the home. To extend blooming and encourage branching, deadheading and routine harvesting are crucial.
How Long Do Zinnias Bloom?
For the garden, zinnias are a popular cut flower because of how long they bloom. From late spring until the first fall frost, zinnia flowers are in bloom.
Are zinnias sun-loving plants?
It’s hot outside, so gardening in the summer calls for plants that are minimal care, drought and heat tolerant, and have vibrant colours.
The better, the brighter.
On each of the three criteria, zinnias were suitable. plus more. They’re among the best flowers that savvy gardeners may use in their gardens, in fact.
If there is a flower that is simpler to grow, please let us know. Since zinnias are annuals, their life cycle from seed to flower to seed is short. Simple garden preparation is all that is needed for zinnias’ arrow-like, pointy seeds to germinate. Simply place them in soil that is well-drained, in full sun, and in an area that receives a lot of summer heat, and you’ll soon see small seedlings and blooming flowers. No enduring can boast of that speed!
One gardening buddy just scatters seeds wherever she wants a few zinnias, watered those areas for a few days, and then lets the zinnias’ naturally easy-to-grow nature take its course.
“Candy Cane,” “Green Envy,” “Persian Carpet,” and “Pop Art.” When a variety has names like those, colour is guaranteed. The ridiculous colour palette of zinnias includes every vivid and pastel shade (aside from blue), as well as bi-, tri-, and crazy-quilt combinations made for cutting, luring pollinators, etc.
Many new zinnia series give options for height and width in addition to vibrant colour.
- While Zinnia elegans tall varieties continue to be the prefered option for the back of the border, shorter series are now challenging the low ground once held by marigolds and petunias. The Thumbelina Series of dwarf zinnias reach their highest point at 6 to 8 inches, whereas the Magellan Series remain roughly knee high at 14 inches.
- The Crystal Series and other creeping or spreading Zinnia angustifolia are a revelation for the front of the border, raised beds, containers, and even ground coverings. The fact that its native to Mexico is even more drought tolerant than regular zinnias makes it the prefered choice for hot locations like sidewalk beds or that no-man’s-land next to the garage.
- With a height of about 8 to 12 inches, ZaharaTM zinnias are renowned for their resistance to powdery mildew and leaf spot (see below). In the entry beds of the Regenstein Fruit & Vegetable Garden, we paired Zahara Yellow, which is brief but sweet, with tiny sunflowers.
Zinnias are obviously meant for the vase because they have style and long, sturdy stems.
The words stars and daisies, dahlias and spiders, buttons and domes, and quill-leaf cactus are all used to describe zinnia blooms. Flowers come in different varieties: “singles,” which have their petals arranged in a row around an open centre; semi-doubles; and doubles. Each one is fantastic in floral arrangements.
The best zinnias for cutting are, of course, the tall kinds; “Benary’s Giant” is renowned for its three-foot-tall, robust stems and huge flowers. Just above a bud joint, angle-cut zinnia stems. Zinnias often stay a long time in a vase; thus, remove all but the most obvious leaves off the stems before placing them in water.
Zinnias require little upkeep. Because they grow quickly, they shade out weeds. They don’t need mulching, and the only fertiliser they need is an occasional application of a well-balanced mix.
Deadheading encourages the growth of additional blooms. Lack of time to deadhead? When it comes to a big bed, the Zaharas indicated in the sidebard are a significant time saver.
The Profusion Series, a cross between Z. elegans and Z. angustifolia, is resistant to powdery mildew, which is the bane of zinnias, just like Zaharas.
Zinnias are accustomed to dry environments because they are indigenous to the grasslands of the southwestern United States, Mexico, and South America. However, wet summers, like the one we’ve had so far, can be damaging. And leaf spot and powdery mildew can result from that. Three recommendations for surviving inclement weather:
- Only water as necessary, and then only at the plant’s base. Wet leaves can encourage the growth of mildew, and water splashing can instantly spread fungus from the ground onto zinnia leaves.
- Taller, mildew-prone kinds can be hidden by foreground plants.
- As one horticultural put it, “Even when zinnias are coated in powdery mildew, they’re covered with flowers,” do both #1 and #2 and accept that zinnia leaves (but not flowers) are impacted by wet weather.
Zinnia seeds can be saved with ease. Simply let the blossoms to completely dry on the stalk, gather the seedheads, and delicately crush them in your fingers to release the harvest of seeds for the following year. In the same manner as other seeds, store in a cool, dry area. (And save some for our seed swap in February of next year in a labelled envelope!)
Last but not least, zinnias attract butterflies, so plant them every year. The plants with larger flowers serve as landing places for butterflies looking for nectar. (The same is true with hummingbirds.) To capture the most attention, try tall zinnias with scarlet or hot pink blossoms.
Living and gardening in Oak Park, Illinois, Karen Zaworski is a writer and photographer who specialises in gardens.
‘Benary’s Giant,’ one of the greatest for cut flowers, stands out in the English Oak Meadow with its 1,000 blooms.
Above: Double Zahara Fire (Zinnia marylandica), one of a group of plants resistant to powdery mildew, was cultivated in the Enabling Garden.
For your summer garden, the ZaharaTM Coral Rose Zinnia (Zinnia Marylandica) excels and requires little water.