When Should You Plant Zinnias

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 late may zinnia seeds be sown?

Zinnia seeds can still be planted now for late summer color that will endure until the first frost. Additionally, they produce stunning cut flowers with a lengthy vase life.

Even the most inexperienced gardener should grow zinnias because they are one of the tried-and-true garden flowers. My first memories of gardening are when I first encountered zinnias. The bush beans and tomatoes set aside for zinnias were a constant source of conflict. My favorite annual flower is still the zinnia, and they now have a prime location next to my back deck where I can enjoy them in the warm weather.

Growing zinnias is simple; they prefer full sunlight and well-drained soil. They may be planted directly in the garden or transferred. Plant them in a peat pot that can be placed directly into the garden or planting bed if you decide to have a head start and want to transplant so as to avoid disturbing the roots.

There are many different types of zinnias. They come in sizes ranging from 6 inches to nearly 4 feet, from dwarf to enormous. The flower heads are available in many different forms, including single and double flowers, spidery shapes, and domes.

The amazing variety of hues is the best feature. The palest pastel hues to the brightest hues are all available in zinnias. They come in solid, multicolored, striped, and specked patterns.

Dead heading zinnias is advised by Michigan State University Extension to ensure flowering from early summer through frost. Zinnias are encouraged to continue performing by dead heading throughout the season. But because zinnias fatigue, I advise putting them in succession every two weeks. I intend to plant in succession beginning in late May and continuing until the first week of July, roughly. This ensures spectacular blooms through the end of September. It’s not too late to plant some zinnia seeds for color that will persist through the first frost in the late summer.

In addition to their amazing garden display, zinnias make fantastic cut flowers and may be used anywhere you need a splash of color. Many zinnia cultivars can stay in a vase for seven to twelve days. The mainstay of the farmer’s market is zinnias as well. Flower farmers would tell that zinnias are one of the most profitable flowers to grow due to their vibrant colors, ease of maintenance, and extended vase life.

The zinnia variants “Benary’s Giant” and “Cut and Come Again” are two of my favorites. Their surnames are biographical. On tall stems that stand between 40 and 52 inches in height, “Benary’s Giant” has huge blooms and dazzling flowers. Cutting the stem just above a bud junction will encourage “Cut and Come Again” to produce continuously throughout the growing season, as will all zinnias.

Do zinnias reappear each year?

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 color 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 center is visible serve to distinguish between these forms:

  • A single row of petals and the center are both visible on single-flowered zinnias.
  • Petal rows abound on double-flowered zinnias, and their centers 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. If the correct circumstances are present, they will develop quite quickly from seed.
  • 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 fertilizer.
  • 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 fully double flowerheads that can be up to 4 inches across and a variety of colors.
  • 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.

Before planting zinnia seeds, should I soak them?

If you’re raising zinnias from seed for the first time this year, you might still have some concerns. Here, I’ll address them for you.

How do you germinate zinnia seeds fast?

To hasten the germination of zinnia seeds, keep the seed trays warm. The biggest effect will be made by heated mats and a warm environment. Zinnia seeds can germinate in as little as five days when the soil is 70 to 75 degrees Fahrenheit, the ideal temperature for germination.

Should I soak zinnia seeds before planting?

Before sowing, zinnia seeds don’t require soaking. The seeds of zinnias are designed to sprout quickly when exposed to water since they are warm-season annual flowers that are indigenous to hot climates like Mexico and the southwest of the United States. Once you sow the seeds and water them, that’s enough to trigger germination.

How long do zinnia seeds take to germinate?

The normal germination time for zinnias is 5 to 10 days. Seeds sown in trays with the soil kept warm at 70 to 75 degrees Fahrenheit using heat mats will germinate more quickly than seeds sown in cold soil, which could take up to three weeks.

Do zinnia seeds need light to germinate?

Zinnia seeds should be placed with 1/4 inch of dirt on top of them because they don’t require light to germinate. The seeds will require intense light in the form of a shop light or grow light as they begin to germinate and break the soil’s surface.

At what temperature do zinnias germinate?

Zinnia seeds should be germinated at 70 to 75 degrees Fahrenheit. The soil will reach these temperatures with the help of a heat mat put beneath the seed trays. In soil that is colder than 70 degrees, the seeds will still germinate, but it will take longer.

Do zinnia seeds need cold stratification?

Cold stratification, which involves chilling seeds prior to sowing, is not necessary for zinnias. The seeds of zinnias are designed to germinate without being exposed to cold because they are warm-season annuals that are native to hot climates.

What time of year do zinnias thrive?

The optimum time to grow zinnia seeds for earlier blossoming is in April or May, either in a greenhouse, cold frame, or on a sunny windowsill. Because zinnias are half-hardy annuals that detest the cold, don’t sow them under cover too early in the spring. Wait until the weather has warmed up enough before planting them outside. That might not happen until early June in colder locations.

Zinnias should not be sown into seed trays since they dislike having their roots handled or broken. Though there are perhaps even better alternatives, module trays are a possibility. According to zinnia seller Sarah Raven, “I use coir Jiffy pellets since zinnias dislike root disturbance” (opens in new tab). In this manner, handling is reduced. In order for the seedlings to slip right out into their planting hole, you can also sow them into lengths of guttering.

To avoid the seedlings drying out, keep the modules, pellets, or guttering well hydrated but never soggy.

Don’t bother with modules or pellets if you live in an extremely cold region (like north Scotland). Instead of planting your zinnias in modules or pellets to be transplanted later, seed them directly into greenhouse beds or the soil underneath a polytunnel and let them to blossom there all summer. This is so that zinnias can flower successfully outside in the summer heat.

Do zinnia seeds germinate in June?

Nowadays, not many flowers are cultivated from seeds, but zinnias are worthwhile. These simple summer annuals reward the grower with colorful flowers up to six inches across that complement both urban and rural gardens and make lovely bouquets.

My summer flower garden last year got off to a late start, with my zinnia seeds not being planted until July. May or June is the suggested time so that plants can establish themselves before the sweltering summer heat.

I went to my local nursery and purchased many packages of zinnia seeds as I hadn’t placed a catalog order. But I also bought some zinnia seedlings in the hopes that they would produce a yield earlier.

To my amazement, the nursery seedlings only blossomed 10 days before my seed-grown plants did, despite having a lead start. Although the blooms in each group were beautiful, the plants grown from seeds cost a fraction of what I paid for nursery plants, and the seeds produced hundreds of plants—many more than I needed.

Zinnias are available in a huge range of shapes and sizes. The huge, cactus-flowered blossoms with mop-headed daisy-like heads are my favorites. The tiny lilliput (pompon) species, whose thickly packed petals resemble parrot feathers, is another favorite of mine.

The Haageana or Mexicana variety features 1 1/2-inch flowers with pointed petals bordered with a contrasting shade, as opposed to the more formal dahlia-flowered zinnias, which have huge blooms with flat petals.

It’s laughably simple to grow zinnias. Children frequently perform on par with skilled gardeners. Contrary to petunias or snapdragons, the seeds are huge, making it easy to seed them and give them the proper spacing.

Make a furrow in the prepared soil that is about 1 inch deep. The seeds should be deposited four inches apart. To prevent the seeds from being washed away, cover with one-eighth inch of soil and water lightly. Till the seeds sprout, which typically takes four to eight days, keep the soil moist. Transplant any surplus seedlings to bare places or pots after thinned to a distance of 10 inches.

Mildew is the main issue with zinnias, especially where I live near the shore. Planting zinnias early enough in the summer to allow them to bloom before late September, when the days start to get shorter and the plants get more damp at night, can lessen its effects. It’s also a good idea to water the roots solely, leaving the foliage dry. Spray a fungicide, such as Funginex, on the leaves at the first indication of a white powder coating them.

I experimented with Z. augustifolia one summer (also called zinnia classic, Z. linearias, or thin-leaved zinnia). Although its 1 1/2-inch golden-orange semidouble blooms were not as eye-catching as modern hybrids’, the plants did have one enticing quality that made them stand out: they did not develop mildew, even in my humid climate.

Now I find that the Z. elegans and Z. augustifolia hybridizers at Burpee have produced a pink, 2 1/2-inch bloom that is supposedly mildew-resistant. In the flower garden this summer, I can’t wait to test this new type, Rose Pinwheel.

I’ll also plant pink cosmos, pink statice, rose cleome, blue salvia (S. farinacea Victoria), rose shades of strawflower, and gloriosa daisies around it. Rose Pinwheel’s gold centers should compliment the gold daisies well, and blue is a great complementary hue in general.

I’ll start the strawflowers in flats a few weeks prior to planting them in the garden because they take longer to flower. The seeds for all the other plants will be planted right in the garden. Although blue salvia is simple to cultivate from seed, it takes several months before it starts to bloom, making it a summer flower that I typically buy from the nursery.

All of my plants will be cultivated next to soaker hoses so that I may use water as effectively as possible. My irrigation system is basic, despite the fact that some irrigation systems are fairly complex (with computer timers and multivalve stations).

I use 150 feet of soaker hose connected to the garden hose for each tier of my garden where annuals are sown. Twice a week, I let the water run gently for about five hours. I may decide whether to apply more or less by keeping an eye on the soil’s moisture level.

Several well-known zinnia strains can be acquired at garden centers for gardeners who like the speed and convenience of seedlings.

The biggest is State Fair, a dependable favorite that has been around for years and is dahlia-flowered. On 12- to 18-inch bushes, the Peter Pan, Pulchino, and Cut-and-Come-Again zinnias yield three-inch flattened blooms. Thumbelina, the smallest zinnia, is adorable but only blooms for a little period of time, making it seem hardly worth the effort.

Zinnias are a favorite of Terry Hartog, who grows thousands of bedding plants for his Vintage Nursery in Lakewood. Because of its relatively big blossom size and compact growth, he prefers a mass planting of Peter Pan that is surrounded by the white vinca Little Bright Eye. The bottom leaves of zinnias can grow unattractive, thus the vinca conceals them.

According to Terry, both vinca and zinnias are suitable for hot climates since they can withstand the heat.

The best assortment of zinnias may be found in catalogues like Burpee Gardens, Warminster, PA 18974 (with zinnias on the cover), and Park Seed, Greenwood, SC 29647-0001. The majority of neighborhood garden centers also carry a range of zinnia seeds.