Zinnias are some of the most colorful and attractive garden flowers. They come in a wide range of colors and varieties and are easy to grow and take care of. In addition, zinnias bloom quite early if temperatures are high and maintain their inflorescences for about 60 days.
Planting zinnias is an excellent choice if you want to give some color to your yard or flower garden without too much effort. They are also very beautiful displayed in vases and floral arrangements.
Further, we will answer some of the most common questions related to the growth and care of zinnias.
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Where Are Zinnias Native To?
Zinnias are American native flowers. Most varieties originate from the grassland areas of North America, but there are also several species that are native to regions of South America.
The “zinnia” genus includes multiple varieties, but one of the most impressive is zinnia elegans. This species produces large blooms, with multiple rows of petals, and with bright colors ranging from white to orange, red, pink, yellow, and purple.
Are Zinnias Annual Or Perennial?
Zinnias are annual plants. They die after each season and won’t come back the following year without reseeding them. However, if you allow the seeds to drop from the dry flower heads in autumn, the ones who get buried in the soil and survive the winter, will germinate and produce new flowers in the spring after the soil gets warmer.
When To Plant Zinnias?
Zinnias should be sowed outside in early spring after the danger of late frost has passed. The seeds will start to germinate in approximately 3 to 5 days if the temperature maintains roughly between 80–85°F (27–29°C) during the day and 60–65°F (16–18°C) at night, according to Johnny’s Seeds.
Although they grow very well from seeds sown directly into the ground, if you want your flowers to bloom earlier, you can first grow them as seedlings, then transplant them into the garden when temperatures reach the recommended levels. Note that they can be sensitive to transplanting. Hence, to limit the stress, it’s recommended to do this operation on a cloudy day when the sun is not very strong.
Are Zinnias Easy To Grow?
Yes, most people agree that zinnias are some of the easiest garden flowers to grow. They are low-maintenance plants that don’t require too much care. They don’t require too much fertilization and can thrive even in poor soils that other plants won’t grow in. Zinnias are also not very susceptible to many plant diseases.
Apart from their beauty, being so easy to take care of is, in fact, one of the reasons why so many cultivate them.
Do Zinnias Need Fertilizer?
In quality soils, zinnias can grow even without fertilizer. For many years I grew these flowers without applying any fertilizer and each time they bloomed spectacularly, although the soil is not of the best quality in the area where I live.
However, in order for these plants to produce the most beautiful flowers and to speed up their blooming process, it is recommended to apply fertilizer from time to time. A well-balanced 10-10-10 all-purpose fertilizer (order one from Amazon) should do the job.
Can Zinnias Grow In Pots?
Zinnias can grow well in pots, but make sure the container has enough drainage holes to enable the excess water to leak out.
You also need to make sure you choose a soil type that doesn’t retain too much water. If it’s soggy permanently, the roots of your zinnias can quickly rot and the plants will eventually die.
Can Zinnias Take Full Sun?
Yes, zinnias can take full sun. Not only do they withstand the full sun, but it is even recommended to grow these plants in an area where they can enjoy plenty of sun and heat throughout the day.
While zinnias can grow in partial shade, they are more prone to developing fungal diseases, and usually bloom less.
How Often To Water Zinnias?
Although zinnias have relatively shallow roots, they are pretty drought-resistant plants. Because they can withstand dry soils better than soggy soils, zinnias don’t require daily watering.
In general, you should water them once every two or three days, but this schedule may vary from region to region and depending on the time of the year.
What Diseases Do Zinnias Get?
Unlike other plants, zinnias are quite resistant to disease. The most common diseases that these plants develop, according to the Missouri Botanical Garden, are powdery mildew and Alternaria blight (also known as zinnia blight).
Powdery mildew is a fungal disease distinguished by the occurrence of a grayish-white powder (similar to wood ash) on the foliage of the plants. Later, it can also extend to stems and flowers.
Zinnia blight (Alternaria blight) is a common disease of zinnias and is caused by a fungus called Alternaria zinniae. Symptoms of zinnia blight include red-brown spots that occur on the upper side of leaves with grayish-white spores that develop in the middle. Eventually, the foliage will turn brown and dry out. In the advanced stages of the disease, the stems and flowers can also be affected.
While these are probably the two most common diseases of zinnias, there are more fungal diseases that can affect them. Some species of zinnias are more susceptible to disease than others.
The most effective treatments for fungal diseases include copper-based fungicides, applied either for prevention or for treating the diseases in their early stages.
Most fungal diseases of zinnias are usually caused by too much moisture or because they do not have enough sun.
Do Zinnias Attract Bees?
Yes, zinnias attract many bees, butterflies, and other insects. Their flower heads produce plenty of pollen which is picked up by bees and other pollinators.
So, if you are allergic to bee stings, or do not want insects near you, you should not plant zinnias close to your house.
On the other hand, bees, butterflies, wasps, beetles, flies, and other pollinators are very beneficial for your garden. They help the plants produce fruits by transferring the pollen from the male parts of the flower to the female parts. Without pollination, plants can produce many flowers, but will not bear fruit.
Therefore, planting zinnias near your garden plants may be a good strategy to attract pollinators. Watch out, however, for the common diseases and pests that may affect both zinnias and the plants in the vicinity.
Zinnias are also known to attract hummingbirds. Hence, if you are an ornithologist or just someone who loves hummingbirds, you may want these flowers near your house.
Do Zinnias Spread?
As mentioned earlier, zinnias are annual plants. At the end of the vegetative cycle, they produce seeds and then die. So the only way these plants can spread is through their seeds.
Therefore, if you do not harvest the seeds in the fall and they drop on the ground and manage to get covered by soil and withstand the winter, the seeds can germinate the following spring and produce new plants that can spread in the nearby area.
Will Zinnias Rebloom After Cutting?
Yes, zinnias will produce new flowers after cutting them, and that is one of the reasons why so many people love them.
Even after you cut the flowers, zinnias will subsequently produce other blooms. However, you need to make sure that when you cut the flowers, you remove the entire stem section and cut the flower just above the leaves’ joint.
Here’s a very helpful video from Renee’s Garden Seeds YouTube channel that covers this aspect in detail.
Do Zinnias Need Deadheading?
Deadheading is a way to make your zinnias produce flowers for an extended period of time by removing the wilted, or damaged old flower heads.
Zinnias multiply by seeds. To produce the seeds, the plant first needs to produce the flowers. Hence, if you cut its flowers, the plant will have to develop others in order to produce seeds and ensure its propagation.
So, deadheading zinnias is a strategy to enjoy the flowers produced by them all season, without the need to grow other plants. Just make sure that you cut the flower head just above a set of leaves, removing any stem leftovers.
Do Zinnias Need Pruning?
Pruning zinnias is not mandatory but is a good way to obtain more robust and bushier plants. This will also help the plant to split and, therefore, produce more blooms.
Normally, most zinnias varieties grow tall and thin. The plants are then susceptible to be knocked over by strong winds or water unless you plant more zinnias nearby to support each other. However, zinnias planted too close will be more prone to developing fungal diseases and suffer from nutrient deficiency.
One way to get stronger zinnia plants is to prune them. This operation will encourage the plant to grow wider instead of taller.
Prune zinnias, when the plants produce their first blooms. Use a garden shear and cut the blooms off above the first ramification from the top.
Below is a video from Hoss Tools that explains the benefits of pruning your zinnias and shows how to do that correctly, without hurting the plant.
Although zinnias are considered some of the easiest plants to grow, there are a few things you need to know in order to enjoy these flowers for as long as possible.
We have tried to answer some of the most common questions regarding the growth and care of zinnias and I hope you’ll find these answers useful.