When To Thin Zinnia Seedlings

Getty Images Carole Gomez

One of the simplest gardening activities of the year might be starting zinnias from seed. Where spring arrives early, don’t directly plant zinnia seeds outside until after the final frost. The seeds should only be sown around 1/4 inch deep. Within four to seven days, seedlings will begin to emerge. To promote air circulation, which is essential for maintaining zinnias in good shape all season, thin the seedlings once they are approximately three inches tall, spacing them 6 to 18 inches apart.

In colder regions, plant seeds indoors four to six weeks prior to the typical last frost date in your region. Before you plant the plants in your garden, harden them off by leaving the trays outside for a few hours each day.

If the zinnia plants you purchase at the garden center are already the size at which the blooms bloom, you can make the transition to your garden easier by cutting the plants back by one-third. After that, relax and watch your zinnia patch develop and thrive.

I have seedlings, when should I thin them?

When seedlings have one to two sets of genuine leaves, they are typically trimmed. The plant is not viable until the next real leaves grow, which will have a very different appearance from the first leaves, known as the cotelydons. The first leaves are embryonic seeds contained in the seeds.

Most plants reach a height of 2 to 3 inches when their first true leaves appear, at which point they are easily pulled out by the stem. After watering, you can thin your seedlings to make it simpler to pull them without disturbing other seedlings if you’d rather pull them than cut them with scissors. Additionally, it’s best to thin in the late afternoon so that the surviving seeds have time to acclimatize overnight before being exposed to heat and sunlight.

In what height should zinnia seedlings grow?

Annual summer flowers known as zinnias were first grown in Mexico and other parts of South and Central America. These daisy-like blooms feature hundreds of small petals encircling a center disc with a golden border and come in a range of vivid colors, including red, orange, pink, purple, yellow, and white.

The height of zinnia plants varies from 12 to 39 inches, depending on the cultivar. All zones have seasonal plant growth.

Does thinning zinnia seedlings make sense?

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 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.

Are thinned zinnia seedlings transplantable?

Most likely, all the flower and vegetable seeds have been planted and are growing, but there is no time to savor your success as a successful gardener. There is a follow-up task that will determine whether the sprouting seedlings succeed or fail. It’s known as thinning.

The removal of extra seedlings is a crucial operation that is frequently postponed or ignored totally in order to give the remaining seedlings a better chance to grow healthily and resemble the pictures on the seed packets or in your seed catalogs.

Gardeners who are just starting out are often put off by the seemingly brutal technique of thinning because they are so excited to witness the early results of their initial seed-sowing endeavor. Why pull out the priceless young plants, they enquire?

But seasoned gardeners are well aware that once a seed has germinated, the seedling starts to take up more and more moisture and nutrients from the soil. Weeds and other seedling competition obstruct the plant’s regular growth.

They understand that a small number of fully developed flowers and vegetables are preferable than a large number of stunted ones that are unable to thrive on only half the amount of sunlight, water, soil nutrients, and space they require. Therefore, thinning can be seen as a chance to let the best plants thrive while getting rid of the less desirable ones.

Almost any row of recently planted seedlings will exhibit the consequences of overcrowding. Where seeds were planted too closely together, the young plants are typically much smaller than those that have more room. It is frequently the case that the seedling at the end of a row or one that emerges from the row where the seed may have been accidentally dropped is larger and better than the others, highlighting the significance of proper spacing.

At the time of planting, it is nearly impossible to properly space many types of extremely small seeds, such as those of lettuce, carrots, turnips, onions, poppies, or petunias. When all they produce are luscious tops, even radishes, whose seeds are not so tiny, can disappoint gardeners. When crowded, carrots, beets, and similar root crops all appear to behave in this way.

It is better to thin gradually because it would be foolish to remove all surplus plants at once when later some might be destroyed by pests, diseases, or accidents. Each will finally stand at the ideal distance from the others as the seedlings mature, giving minimal potential for vacancies in the row.

Some vegetables are particularly appetizing when they are young. There may be enough half-size, fragile, gourmet produce from late thinnings to enjoy until the developed harvests are ready for harvest.

One example of this is lettuce. It will soon grow to a size where alternate plants can be cut for early salad delights. Initially thinned to stand around an inch apart. One more is beets. Green beets can be grown from young plants that have been removed from the row and trimmed down.

Annual flowers grown from seed, such as zinnias, alyssum, marigolds, and asters, will readily accept transplanting of seedlings of any size. Simply transplant them right away where you want them to grow, give them plenty of water, and if the sun is really hot, give them some light shade for a few days.

After a rain or after hose-watering seedlings, is a good time to thin them. The young plants will then be able to readily emerge from the ground without damaging the delicate roots of nearby ones that are still in the rows or even those that were removed with the aim of transplanting them elsewhere. The majority of seed packets specify the distance between seedlings after the last thinning.

If allowed to grow too tall, A-Grass may experience some temporary damage from heavy shading. After mowing, yellow areas show this. Turf tips may also go brown due to bruising rather than clean cuts from a loaded or equipped with dull blades mower. It’s a good idea to mow frequently enough to prevent more than one-third of the grass from being removed at once.

A woody perennial called wild ginger (Asarum) does well in a shady environment with moist, humusy soil. By using creeping root stocks, the plants spread quickly, and the kidney-shaped leaves make for an intriguing ground cover.

What occurs if seedlings are not thinned?

Seedlings that are crowded together will compete with one another for nutrients, water, air, and root space if they are not thinned. You don’t want to deprive your seedlings of those items! Crowding seedlings not only raises worries about competition but also raises the risk of illness. The diminished airflow between the plants is mostly to blame for this. Powdery mildew is a pest that thrives in confined spaces and spreads spores when leaves scrape against one another. All of this is true for both indoor container-grown seedlings (or plants) and outdoor garden-grown plants.

It is ideal to hold off for a few weeks after sprouting, until the plants have grown one or two sets of genuine leaves, but not for too long. After the initial batch of sprouting leaves, the “real leaves” appear. The very first ones are the embryonic leaves, or cotyledons, which are frequently heart-shaped and interchangeable among many plant species. The real leaves more nearly resemble the smaller versions of the mature plant’s leaves. Once a couple of those sprout, it aids in identifying the seedlings with the best appearance.

When it’s time to thin, you get to decide which seedling is the sturdiest, healthiest, and prettiest to keep around. The chosen keepers will flourish after the thinning! In just a few weeks, seedlings can swiftly grow to be four times the size of the ones that were left unthinned! Leaving them unthinned severely hinders their development. This is something I’ve tried out and personally experienced many times!

This is somewhat up to personal preference, like many gardening-related matters, but I’ll discuss the two techniques we typically employ: pruning and gently separating.

A third choice is to hand remove the undesirable seedling from its container, often with the intention of keeping the seedling plucked to replant. Since it can be a little risky, we don’t employ or encourage this approach. The seedling you are intending to save and leave behind in the container may also suffer harm or be totally pulled up with the pulled seedling, defeating your efforts to save it.

Trimming out the undesirable seedlings is our favorite approach for thinning most types of seedlings. With small, sharp trimming scissors, we just cut the smallest, thinnest, or leggiest ones off at the root line, leaving the chosen one behind. We have many pairs of these trimming scissors since we adore them so much! On this homestead, they are commonly employed for a variety of tasks.

We thin almost all of our vegetable seedlings in this manner, whether they were seeded outdoors or in containers. We just don’t need to save the extra ones, in addition to trying to limit potential damage. What in the world were we going to do with all those extra saved plants, given the restricted room in the raised garden beds and under the lights in the greenhouse? As additional insurance, we already start more than we plan to grow. On top of that, we cannot fit dozens more tomatoes, peppers, or squash.

Advantages of trimming

It prevents unintentionally dispersing the one you’ve decided to keepthe strongest and thickest appearing chick by cutting rather than pulling. There is no need to pot anything up or plant anything out at the same time because we are not aiming to keep the ones we have thinned out by cutting (as you may do if you are separating them, explained below). This makes the trimming-based thinning procedure incredibly rapid and simple! All we have to do is cut, then continue.

Notably, we start the majority of our vegetable seedlings in 6-packs or 4-pots rather than tiny peat pellets or smaller cell packs, which lessens the need to pot them up right away. As a result, trimming is even more enticing to us because there is no need to fuss over the plants when thinning. After being thinned, the plants will all be content in their homes for a long time.

Potential Drawbacks:

Some individuals consider the death or loss of these extra seedlings to be a bad thing, an undervalued opportunity for future plants, or even a waste. However, this is not how we see it! Why is this:

Microgreens!

Even though we don’t replant the ones we cut, they don’t “go to waste”! The thinnings are micro-greens that are rich in nutrients. We consume them. at least the majority of them.

Which seedlings can you eat? So many varieties! To give you a few examples, edible microgreens include any young greens like lettuce or kale, other brassicas like broccoli or kohlrabi, or essentially any vegetable that you could otherwise eat the leaf of! A more comprehensive list can be found below.

These are great as a salad or dinner topping! Although they can be cooked, we often use them raw. They also produce a really upscale chicken delight. Microgreens retain their most flavor and freshness when stored in the refrigerator in a sealed container, such as a glass Tupperware or ziplock bag, along with a small amount of water.

Here is a list of edible seedlings, and also those you want to avoid consuming

Separating seedlings with care is another way to thin them. To do this, gently remove the seedlings, roots, and entire chunk of soil from the tiny container. The mass may usually be eased out of the container by gently turning it on its side and pressing up from the bottom as necessary. Keep your hands off the seedlings themselves!

Pull apart the seedlings while gently separating the soil. If the roots are knotted together, take care to avoid aggressively ripping them apart. Then, after they have been hardened off, either immediately re-pot the ones you wish to save or get them planted outside! (Post on hardening off is coming next week.)

For flower beginnings like zinnias and sunflower seeds, I utilize this technique most frequently. In my humble opinion, the garden always has more space for flowers! Zinnias in particular, as they are a favorite of monarchs! I prefer to attempt to save as many of those babies as I can. They can tolerate this therapy because they are often quite tough. Additionally, we often start our flower plants a little early and smaller than our vegetable beginnings. As a result, I won’t need to repot them when I separate them and can simply plant them outside. Fava beans are used in the same way. For a little while longer, the peppers and tomatoes in the greenhouse need to be watched for.