How To Trim Zinnias

I was apprehensive about cutting back my tiny Zinnia plants. Everyone advised cutting them back to help them branch out and produce more flowers, and after doing a lot of research and watching several videos on YouTube, I decided to follow their advice. I shuddered and removed them all. Let me tell you, cultivating zinnias was the best choice I ever made! They multiplied like weeds! I have enormous, overgrown plants that have simply continued to bloom all summer!

Zinnia plant pruning is quite simple. Simply wait until they are between 10 and 12 inches tall; you want to ensure that they have a few sets of leaves. You should remove the plant tops when they get to this stage. With a good pair of pruners, I removed the top two sets of leaves by about 4 inches. (See the image above) It’s that simple to prune zinnias!

Do zinnias bloom again after being deadheaded?

One of the most crucial tasks in learning how to cultivate zinnias is to deadhead the blooms in order to keep your plants in bloom. By extending the blooming period of the plant, deadheading zinnias encourages the flowers to continue to bloom.

Cutting back the Zinnia flower heads after the blooms start to fade can encourage fresh growth. Because of their incredible hardiness, zinnias can be deadheaded without causing any damage to the plant.

Decide how far back you want to trim the stem to deadhead zinnias. Then, make a precise cut immediately above a row of leaves using a pair of sharp garden scissors. The plant will be encouraged to grow new stems and blossoms where you cut if you do this.

Do I need to remove the blossoms off my zinnias?

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.

My zinnias are leggy; why?

Leggy seedlings are mostly brought on by a lack of light. It may not be enough light coming through the window where you are growing your seedlings or the grow lights you are using may not be close enough to the seedling. The seedlings will become leggy either way.

This occurs as a result of how plants respond to light naturally. Plants always expand toward a source of light. The same factor that causes crooked houseplants also causes leggy seedlings. The plant strives to heighten itself in order to get closer to the light because it is too far away for it to survive as it grows in the direction of the light. An unfortunate fact is that a plant can only grow so much. The width of the stem is sacrificed in order to acquire height. You end up with lengthy, floppy seedlings as a result.

There are various reasons why leggy seedlings are a concern. First, moving seedlings outside will present challenges if they are too tall. They can’t withstand weather conditions like wind and heavy rain as well because they are thin and floppy. Second, weak seedlings have a difficult time developing into powerful plants. Thirdly, seedlings that are toppling over may be more susceptible to illness and pests.

Do zinnias return the following 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.

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.

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.

When will zinnias bloom again?

Since zinnias are annuals, their growing season is limited to only one. However, they make up for their short lifespan with blossoms.

All summer long, zinnias generate a ton of blossoms. The blooms give a splash of color to any garden since they are vibrant and happy. Additionally, the blooms are beneficial to the ecosystem since they draw pollinators like bees and butterflies.