The appearance and type of zinnias, which come in single and double flowers and grow from eight inches to four feet tall, vary widely. There are zinnias with flowers that resemble dahlias, cacti, beehives, and buttons.
The flowers come in a variety of hues, including white, yellow, pink, red, lavender, and green. The lovely plants are preferred because they attract butterflies, which are important for garden pollination. No matter what variety of zinnia you cultivate, it will require a position with full sun because it will encourage the plant to blossom more and develop healthily.
Instead of heavy, deep garden soil or clay soils, zinnias require well-drained soil. Turning and loosening the soil in the bed where you intend to plant zinnias, adding compost to increase organic matter and peat moss and sand for drainage are all necessary soil preparation steps.
Planting Zinnias
The majority of the time, zinnias are sown as seeds outside because they thrive in warm climates and bloom for a long period of time throughout the growing season. After the last date of frost, they can be planted in the ground or in the garden.
Additionally, you can grow zinnias indoors from seed by sowing them in flats or a seed-starting medium four to six weeks prior to the last anticipated date of frost. Keep them at a temperature of between 75 and 80 degrees Fahrenheit and under artificial lighting. In 6 to 10 days, seeds ought to start to sprout.
In the spring, wait to plant seedlings outside until the weather is consistently warm because they suffer in colder climates. You won’t need to bother about saving seeds or transplanting most zinnias the following year because they typically reseed themselves pretty successfully.
Zinnia Care
Because zinnias are heavy feeders, plan to fertilize them frequently and regularly to promote lush, vibrant blooming. For the first spring planting treatment, use a balanced 10-10-10 or 6-6-6 fertilizer and apply about one pound per 100 square feet.
Zinnias will bloom well into the fall if you fertilize them, so you can apply another dose of fertilizer in the middle or late summer. All zinnia varieties benefit from deadheading, or pinching off the dead flower blossoms. If you want to encourage yours to grow into a bushy, compact form, you can also pinch off the growing tips that try to shoot upward.
Alternately, plant your zinnias closer together and nip off lower shoots to promote tall growth if you want to cultivate them with long stems for cut blooms. Regularly water zinnias to keep the soil moist, but do not overwater. In hot climes, drink more water.
Zinnia Pests & Diseases
Powdery mildew is zinnias’ most frequent issue. Make sure there is adequate airflow around the plants and that they are not too close to one another to avoid it. Since mildew prefers chilly, moist environments, water during the day rather than at night.
To avoid water sitting on leaves and stems, water carefully, directing the water into the soil at the plant’s base. Since powdery mildew is so prevalent, some zinnia producers also apply fungicide as a prophylactic measure before it appears.
Additionally, hybrid zinnia cultivars that are resistant to mildew are now available. Alternaria, often known as leaf spot, can also affect zinnias but can be avoided with enough airflow and routine deadheading. To stop the spread of disease, you should also pinch off any infected, dying, or damaged plant parts and throw them away.
Aphids and spider mites are the two insect pests that are most likely to affect zinnias. Pick them off by hand, or use a focused stream of water from a spray bottle to wash them off the pants. Do this during the day so that any leftover water quickly evaporates. Insects can be controlled with routine fertilization and watering.
Watering helps combat hot, dry weather, which fosters ideal circumstances for bug pests, while fertilizer fortifies the plant.
How frequently should zinnias be fertilized?
It’s hot outside, so gardening in the summer calls for plants that are minimal care, drought and heat tolerant, and have vibrant colors.
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, color is guaranteed. The ridiculous color 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 color.
- While Zinnia elegans tall varieties continue to be the preferred 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 preferred 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 center; 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 fertilizer 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 labeled 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 specializes 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.
When do my zinnia seedlings need fertilizer?
Zinnias can be grown from seed that is sown early indoors and moved outside after a frost, or from potted plants or seeds sown directly in the ground after a frost.
Indoor Seed Sowing
- Utilizing a seed starting kit, sow indoors 5-7 weeks before to the date of outdoor planting in the spring.
- plant seeds A quarter-inch deep in seed starting solution
- At 70–75 degrees Fahrenheit, keep the soil moist.
- The seedlings appear in 7–10 days.
- As soon as seedlings appear, give them lots of light on a sunny windowsill or grow them 3–4 inches beneath 16–hour-per-day fluorescent plant lights that are off for eight hours at night. As the plants get taller, turn up the lights. Because they will become too hot, incandescent bulbs will not function in this process. Do not leave lights on continuously for 24 hours; most plants need a time of darkness to flourish.
- when they have two sets of leaves, thin to one seedling per cell.
- Seedlings don’t require a lot of fertilizer; feed them when they are 3–4 weeks old with a starter solution (half the strength of an indoor plant food), as directed by the manufacturer.
- After the first frost, transplant hardened-off seedlings into the garden.
- Seedling plants must be “hardened off” before being planted in the garden. By relocating young plants to a protected area outside for a week, you can acclimate them to outside circumstances. At first, be sure to shield them from the wind and the light. If frost is expected at night, cover or bring pots inside; then, in the morning, reintroduce them to the outdoors. The plant’s cell structure is toughened during the hardening off process, which also lessens transplant shock and scorching.
Direct Sowing in the Garden
- After any threat of frost has passed, direct-sow seeds in ordinary soil in full sunlight.
- The top 6 to 8 inches of soil should be cleared of weeds, and then it should be leveled and smoothed.
- The majority of plants do well in soils that have had organic matter added. Compost is a beautiful organic material that can be applied to your planting area whenever you like. It has the perfect pH level and nutrient balance. If compost is not available, topdress the soil with 1-2 inches of organic mulch after planting; this mulch will break down into compost over time. Following the growth season, a soil test will reveal what soil amendments are required.
- equally space the seeds 12 inches apart, then top with 1/4 inch of fine dirt.
- Lightly press the soil with your hand, water, and maintain a uniform moisture level.
- In 7–10 days, seedlings will start to show.
- When seedlings are 1-2 inches tall and 8–24 inches apart, depending on the variety, thin them.
Gardening: Planting
- Choose an area with good, rich, moist organic soil that receives direct sun.
- Turn the soil under to a depth of 8 inches to prepare the bed. To get rid of grass and stone clumps, level the area using a rake.
- For each plant, create a hole that is sufficiently large to hold the root ball.
- Set the top of the root ball so that it is level with the dirt around it. Up to the top of the root ball, cover with soil. Your hand should firmly push the earth down, leaving a small depression to hold water around the plant.
- Water deeply until a puddle appears in the saucer you have made. As a result, there is strong root-to-soil contact and the plants become established.
- Use the plant tag to indicate its location.
How to Grow
- Keep weeds under control while the plants are growing. Weeds compete with plants for water, space, and nutrients, therefore keep them in check by frequently cultivating or by using a mulch to stop the germination of their seeds.
- Mulches also support stable soil temperatures and moisture retention. Shredded leaves used as an organic mulch for annual plants give the bed a more natural appearance and, as they decompose over time, enrich the soil. Mulches should never be placed on a plant’s stems to avoid potential decay.
- During the growing season, make sure plants are well-watered, especially during dry spells. The growing season requires roughly 1 inch of rain every week for plants. To determine whether you need to add water, use a rain gauge. The optimum irrigation method is a drip or trickling system that releases water at low pressure directly into the soil. To reduce disease issues, water early in the day if you want to use overhead sprinklers so the foliage has time to dry before dusk. Maintain a moist but not saturated soil.
- Some protection from strong winds and intense sunlight may be required until plants grow established. Additionally essential is good airflow.
- A mild fertilizer can be administered after new growth starts to show. To prevent burn damage, keep granular fertilizers away from the plant’s top and leaves. Use moderate amounts of a slow-release fertilizer because greater amounts could promote root rots.
- Unless you are growing them purely for cut flowers and want long stems, pinch young plants to induce branching.
- To prolong plant flowering till fall, remove spent flower heads. Cutting zinnias fosters the emergence of fresh blooms and they make excellent cut flowers.
- Observe for illnesses and pests. For advice on pest management measures that are suitable for your area, contact your cooperative extension service.
- In order to prevent disease problems the next year, remove plants that have been killed by frost in the fall.
Growing Tips
- Zinnias can be arranged in tiny clusters alongside perennials or in mixed plantings with other summer annuals. They thrive in cottage and kid-friendly gardens, and cutting gardens frequently cultivate them.
- For containers, shorter zinnia cultivars are best. Be careful not to crowd them because the plants may grow taller and the blossoms may be much less than they should be. Never use garden soil instead of commercial potting mix, and make sure the containers have enough drainage. Plants growing in containers will need more water and fertilizer; keep an eye out for wilting or nutrient deficiencies.
- For cut flowers, trim stems before the blossom opens.
- Hummingbirds, butterflies, and beneficial insects are drawn to zinnias.
Common Disease Problems
Alternaria Leaf Spot: On the upper surface of the leaves and along the midrib, small, rounded, reddish-brown dots with white to gray centers appear. The lesions could surround the stems and result in wilt. Warm, rainy, or extremely humid conditions makes this sickness worse. Avoid getting water on the foliage, advises Burpee. Avoid working with moist plants and remove any contaminated plant components. Make sure there is lots of air movement. For advice on fungicides, get in touch with local cooperative extension service.
Aster Yellows: Plants grow excessively, become stunted, and develop witch’s brooms. Their petals also turn green and become malformed. Leafhoppers propagate this virus-like ailment. Burpee advises removing and destroying diseased plants. Eliminate leafhoppers. Eliminate any weeds in the area that the illness can also live on.
Bacterial Leaf Spot: The earliest symptoms are small, translucent spots with a wide, yellowish edge. Over time, these spots gradually get larger and develop an angular or irregularly circular shape with a reddish center. It flourishes in cooler climates. Flower heads may be impacted by the disease and become deformed. Burpee advises getting rid of diseased plants. Crop rotation should involve diverse family plants. Avoid watering from above. When plants are damp, stay away from them.
Botrytis: This fungus turns flowers, leaves, stalks, and buds a greyish color. It thrives in chilly, rainy weather. Burpee advises removing the damaged plant sections, avoiding watering at night, and not watering directly on the plant. Make sure plants receive adequate airflow. For advice on fungicides, get in touch with local cooperative extension service.
When the weather is humid, a fungus illness known as powdery mildew develops on the tops of the leaves. The surface of the leaves seems to be white or grayish, and they may curl. Burpee advises giving the plants adequate air circulation through optimum spacing and pruning in order to prevent powdery mildew. For advice on fungicides, get in touch with local cooperative extension service.
Common Pest and Cultural Problems
Aphids: These disease-transmitting sucking insects that feed on the undersides of leaves might be green, red, black, or peach in appearance. On the foliage, they deposit a sticky substance that draws ants. Burpee advises attracting or introducing aphid-eating predators like lady beetles and wasps into your garden. You can also use an insecticidal soap or a powerful spray to wash them away.
Leafhoppers: These insects damage leaves and retard growth. Moreover, they spread sickness. Burpee advises clearing up plant detritus. Use soaps with insecticides. For additional advice on insecticides, contact local cooperative extension service.
Burpee advises hand-picking Japanese beetles in the morning into a pail of soapy water.
Compared to what is typical for the variety, plants are shorter, and blossoms are much smaller: Overcrowding can cause zinnias to become stunted and produce smaller flowers. Always adhere to the spacing guidelines for each variety.
Spider mites: These minuscule insects, which resemble spiders, are approximately the size of a peppercorn. They can be yellow, brown, black, red, or black. They ingest plant liquids, sucking out chlorophyll and injecting poisons that leave the foliage with white spots. On the plant, webbing is frequently seen. They cause the leaf to stipple, dry, and become yellow. They proliferate swiftly and do best in dry environments. Burpee’s Advice Every other day, a strong spray can help control spider mites. Try using insecticidal soap or hot pepper wax. For advice on miticides, contact your local Cooperative Extension Service.
FAQ
Is it better to start my zinnias outside or inside? You can either start zinnias inside or outside, in the garden. You can get a head start by beginning them indoors if you have suitable indoor growth conditions, such as plant lights and a heat mat for germination. However, because zinnias are simple to grow from seed and bloom quickly, some gardeners may find that direct sowing is a superior alternative.
Is it possible to cultivate zinnias indoors? Zinnias may not thrive in many homes since they need full sun and high temperatures to develop effectively. In the summer, shorter varieties can be tested in a warm sunroom.
How should I take care of the cut zinnia flowers? When you cut your flowers in the garden, bring a pail of water with you, and as soon as you cut the flowers, immediately submerge them in the water. They will be able to absorb water through the newly sliced stem as a result. More surface area for the water to absorb when cut at an angle. Keep them away from the sun’s rays.
Do my zinnias need to be staked? Staking may be beneficial for taller kinds, especially if they are in a windy environment.
Why do my zinnias have much less flowers than I imagined and are tall and lean? Zinnias will grow tall plants and much smaller flowers if they are planted too near together. Always adhere to the planting instructions’ suggested spacing.