Zinnias are certain to blossom profusely from summer until the first frost, regardless of whether you planted them in your raised-bed kitchen garden, flower beds, or in-ground pollinator garden. (If you’re not receiving as many zinnia flowers as you’d like, try following these suggestions to boost bloom production.)
Take a fresh pair of pruners and trim the stems beneath the blooms as soon as you see that they are beginning to wilt or look exhausted (as though their time in the garden is coming to an end). The best time to harvest flower heads in the Chicago area is in late September or early October, when the weather is getting colder and the blooms appear to be past their peak. You can likely continue to enjoy your blooms for several more months if you reside somewhere with a warmer winter.
Step Two: Let zinnia flowers dry
For about a month, hang your flowers upside-down to dry until they are entirely desiccated. If there is any moisture present when you store them, mold could develop.
Step Three: Store dried zinnia flowers over winter
You have two options: either remove the petals and save the seeds in seed-saving packets, or keep the dried petals on and just put the whole blooms in a Ziploc bag. The neat thing about this is that when it’s time to plant, you’ll be able to determine by the dried petals what color the future blossoms will be.
Step Four: Separate the zinnia seeds from the petals
Many seeds are present in each flower head, which you can separate by rubbing them between your fingertips. Each little spear-shaped seed would already be detached from the petal if you were to purchase a seed packet. It’s okay if the seeds are more tan than gray because they might not germinate. Still have a ton of it!
Step Five: Sow your zinnia seeds
Wait until the last threat of frost has passed before you even consider planting zinnia seeds. If you still have at least 60 (ideally 75) days until your first frost and you still want to enjoy some zinnia flowers this year, you can plant one cycle of seeds.
Choose a location that receives full light in your raised garden beds, a flower bed, or an in-ground pollinator garden. For maximum bloom, zinnias require at least 8 to 10 hours of direct sunlight.
You can plant zinnias utilizing what I like to refer to as the lazy woman’s method (trademark pending… just kidding). In order to plant in this manner, you practically shake the seeds out of your palm.
If the seeds are still attached to the petal, which is intended to enable the seeds be dispersed by the wind, use a small shovel or hand rake to cover them up a little. Give your seeds plenty of water.
If you’re the organized sort, you might use the colors of the petals you collected to grow an ombre field or a rainbow display of zinnias.
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Wait for the Zinnia Flowers to Dry Before Harvesting
The zinnia flower heads should be allowed to finish drying on the plant. When a bloom is ready to be picked, it will be dry to the touch and dark brown in color. An early attempt to harvest a blossom will provide immature seeds that won’t sprout.
Cut or remove the dried zinnia blossoms from the plant. Unless you don’t mind a combination full of surprises, make sure to keep kinds separated and labeled!
Harvested seed heads should be placed on a screen to dry completely on all sides. Depending on the moisture content and seed head, this could take a week.
Release the Zinnia Seeds
On a clear, level surface where you may work to collect the seeds, spread some paper towels. A paper plate should be placed there, and the variety name should be marked with a marker immediately on the plate.
To release the seeds from a dried zinnia bloom, gently “flail” the blossom, peel it apart, or rub it between your fingers over a paper plate. The arrow-shaped seeds are tiny. Some may still be joined to a petal’s base. In that instance, carefully remove the seed. Repeat this procedure with each dried flower you have, tossing the petals and saving just the seeds. Keep the different types apart.
Store the Zinnia Seeds
After the seeds have dried, store them for later use in a paper bag or envelope. Unless you don’t mind combining different zinnia varieties in your garden, separate the seeds for each variety if you have many. To help you remember what’s inside each envelope, label it.
Put the seed envelope in a glass jar with a lid and keep it out of direct sunlight in a cool, dry area. The closet works best. You can plant your seeds outside once the threat of frost has passed for the upcoming growth season.
How can you tell if zinnia seeds are high-quality?
Pinch a green zinnia seed between your finger and thumbnail to determine its viability. If it feels difficult, you could have a good seed. Next, lightly scratch the seed coat with your thumbnail. The coating should scratch off in little pieces. Your seed has an embryo if you notice a white “nut inside, and this should suggest an excellent possibility of germination.
When the season is over, what should you do with zinnias?
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
Zinnias are annuals, so they’ll grow for one season to produce flowers and seeds, but the original plant will not come back in subsequent years. 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 totally double flowerheads that can be up to 4 inches across with 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.
Do zinnias reproduce on their own?
Will Zinnias Self-Reseed? Here, the quick response is “yes” There is a fair possibility that zinnia seeds will germinate and thrive the following spring if the plants are allowed to blossom and set seed.
How are zinnia seeds distinguished from chaff?
Obviously, eliminating the chaff is as simple as explained above if you are growing naked grains. Remember that the weight of the seeds and the chaff must differ significantly for this method to be effective. To separate the chaff from the seeds, a fan can also be used. Lay a tarp on the ground before winnowing in this way. A baking sheet should be placed on the tarp, and the seed should be slowly poured onto the baking sheet from a few feet (1 m) above. Repeat as often as required until no more chaff remains.
“Roll and fly” is another technique for separating the wheat from the chaff. Round, ball-like seeds perform well. Again, moving air is used to clean the seeds, but the finest tools are a fan, your breath, or a cool blow drier. In the middle of a sheet or tarp, place a flat box. A cookie sheet should be placed on top of the box, followed by the seed and chaff. Lift the end of the cookie sheet and turn on a fan to blow air across it, causing the seeds to fall. Repeat as necessary until the chaff blows off.
Sieves can also be used to separate the grain from the chaff. Place the sieves in a stack, with the largest on top and the smallest below. Shake the seed and chaff mixture into the smaller sieve after pouring it into the upper sieve. The chaff should stay in the larger sieve, while the smaller sieve should gather the seed.
There are other, less complicated techniques for sorting the grain from the chaff, no doubt. However, since this method of winnowing can take some time, it could be good to have a friend or two help if you have a larger crop of seed that has to be sorted.
Zinnia seeds—can they be frozen?
Because zinnias are sensitive annuals, they cannot withstand cold temperatures. After the risk of frost has passed and the earth has begun to warm up, plant them in the spring. Four to six weeks before the latest day of frost in your area, you can either direct-sow the seeds in the garden or start them indoors.
- are real annuals, having life spans that are exactly one year long.
- They will produce an abundance of blossoms from early summer until frost kills them in a site with full light and well-drained soil.
Gardeners frequently dead-head zinnias in order to promote repeat blooming. However, you should leave some of the blossoms on the plant so that they can mature into seed pods if you want to save seeds.
Zinnias will self-seed in gardens in warm climates where the temperature doesn’t frequently drop below freezing. Zones 10 and higher of the U.S. Department of Agriculture’s plant hardiness scale are included. In the spring, seeds that have been exposed to frigid temperatures hardly ever sprout.