How To Grow Zinnias From Cuttings

Stem cuttings are a simple way to propagate zinnias and create new plants. In just a few weeks, the cuttings can be planted after being rooted in water.

For more information on the ideal growing circumstances, pinching, deadheading, and seed preservation, visit the article 7 Best Tips For Growing Zinnias.

Can zinnias be rooted in water?

Stem cuttings are a simple way to propagate zinnias and create new plants. In just a few weeks, the cuttings can be planted after being rooted in water. For more information on the ideal growing circumstances, pinching, deadheading, and seed preservation, visit the article 7 Best Tips For Growing Zinnias.

Do zinnias regrow after being cut?

The extreme heat and dry conditions have forced many growers to scramble to tend to and harvest their stressed fields and gardens, including here on our farm in the Skagit Valley and throughout much of the Western United States. While many flowers bloom profusely in this kind of weather, it is crucial to know the optimum times to harvest and ways to care for your fresh cut blooms immediately after they are cut if you want your flowers to last as long as possible—especially with the added stress of high temperatures. (This is referred to as “stage of harvest” and “post-harvest handling” in the language of flower farmers.)

Here are some of my favorite hints for avoiding heat waves and getting the longest vase life possible from 10 high summer flower varietals.

Zinnias: To ensure a long vase life, zinnias must be harvested at the proper time. Wait too long, and the blossoms will swiftly fade; harvest too soon, and the stalks will sag and droop. The “wiggle test” is a pretty easy way to determine whether your zinnias are ready for harvest. Simply take hold of the stalk a few inches below the flower and gently shake it. The stem will be delicate and flexible if it is young. When you wriggle the stem, it should stay rigid and straight if the plant is ready to be harvested. Cut time has come! To create a long, sturdy stem, deeply cut the plant. Don’t be hesitant to clip off lateral sprouts on the main stem you just plucked; remove the foliage as well. Because zinnias are “cut and come again” flowers, they will continue to grow all season long even after being severely pruned.

We cut zinnias and place them directly into clean, fresh water that has either been supplemented with a drop of chlorine or a CVBn pill. The little conditioning pills, which are frequently marketed for gerber daisies, are actually ideal for all of the “dirty flowers with hairy stems that easily gather dirt and bacteria that can muddy up the water.” The hottest time of the year is when zinnias blossom continuously, and they also enjoy heat throughout the post-harvest period. One of the few flowers we don’t treat in the cooler before delivery or design work is this one. Simply said, we keep them out of direct sunlight in a dark, shaded area of our studio. These few easy steps will give you gorgeous, long-lasting blossoms that last 7–10 days in a vase.

Note: In general, certified organic agriculture does not permit the use of commercial flower food. Using bleach or hot water and harvesting at the right stage are crucial if you have certification. To give your flowers the longest possible vase life even if you are not certified organic, CVBn tablets and other hydration and conditioning options are worth the extra money.

Basil: During the height of the summer, we nearly always add at least one or two stems of Cardinal, Oriental Breeze, Lemon, or Cinnamon basil in our mixed bouquets of flowers for grocery store clients. When the flower heads start to appear and the stems start to harden, I pick the basil. To keep them from wilting, I treat them with Quick Dip (a non-organic alternative) or boiling water (an organic alternative). As these plants wilt quickly, be cautious to harvest them in the cool of the morning or evening. Basil doesn’t like the cold, just like zinnias, so keep them out of the refrigerator to finish their conditioning. The vase is frequently where stems root, and they should last 7 to 10 days.

The fuzzy, aromatic leaves of scented geraniums are a must-have for bouquets, but if you don’t take a few simple precautions, they could wilt easily. In order to avoid the heat of the day, I always attempt to trim the scented geraniums first thing in the morning. I sliced them, placed them in cool water, and gave them 3–4 hours to rest and condition before arranging them. Dip the bottom 2-3 in boiling water for 5-7 seconds or dip the stems in Quick Dip if they are still wilting.

Another flower that is prone to wilting is the hydrangea. Perhaps more significant than the harvesting stage is how you hydrate the produce after it has been sliced. My secret is to cut them when they are still chilly, use Quick Dip quick hydration solution, or cut them into hot water for organic production. I am familiar with some flower growers who swear by dipping the just-cut stems in alum powder (found in the grocery store’s spice aisle), while others would soak the entire bloom in water before use to prevent wilting.

Cosmos: Cosmos generally don’t have a very long vase life, but if you cut them at the proper point, you can extend their beauty. Cosmos should be cut when just one petal is beginning to unfold, and once that happens, let the vase’s other buds and blossoms bloom.

Sunflowers: Harvesting the blooms just as the first few petals begin to lift off of the central disk and removing all but the top few leaves will give your sunflowers the longest vase life possible. This can be challenging for beginners since it still appears to be “closed” and not ready to pick, but if you cut them early, you can prevent bug damage and enjoy longer vase life. These people, who are referred to as “dirty flowers,” may benefit from some bleach in the water or from being cut into a pail of water that has been CVBn-treated.

Celosia: When harvesting crested celosias, also known as “cock’s comb,” wait until the crests are fully grown (or a bit sooner is good too), but before the plant begins to produce seeds. Before plucking celosias with feathers, let them stretch and become feathery. Make sure to remove around 3/4 of the leaves after cutting and submerge them in cool water.

Cerinthe: Harvest during the coldest part of the day, then immediately treat stems by putting the bottom 2-3 inches in boiling water for 7–10 seconds, followed by a cool water bath. After harvest, stems become extremely floppy, but once hydrated, Cerinthe can last up to a week in a vase.

Harvest rudbeckia when the flowers start to unfold. Black Eyed Susans are infamous for fast turning their water murky. By reducing this and extending their vase life, you can expect a vase life of 7 to 10 days by adding a few drops of bleach to the water.

If you have any more advice or methods for gathering high summer blossoms and extending their vase life, please let me know. Please share any more advice in the section below.

Can zinnias be grown indoors?

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 an 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.