Zinnias are bright, cheery members of the daisy family, closely related to the sunflower. Zinnias are popular with gardeners because they’re so easy to get along with, even in climates with long, hot summers. Like many summer-blooming flowers, zinnias are annuals, meaning they germinate, bloom, set seed, and die in a single year. They typically aren’t well-suited for the indoor environment, and the idea of zinnias as houseplants may not be realistic.
However, if you’re interested in trying your hand at indoor zinnias, go ahead and give it a shot. Potted zinnia flowers may live a few months indoors, but don’t expect zinnias as houseplants to survive indefinitely. Here are some tips for indoor zinnia care.
Indoor Zinnia Care
Although you can grow zinnias from seed, it’s easiest to start with small bedding plants from a garden center or nursery. Look for dwarf zinnias, as regular varieties can become top-heavy and may tip over.
Plant in a container filled with good quality potting mix. Add a generous handful of sand to improve drainage. Be sure the container has at least one drainage hole in the bottom, as the plants won’t last long in soggy growing conditions.
Outdoor zinnias get plenty of bright, natural sunlight, and even your brightest window may not provide enough light. You’ll probably need a high-intensity grow light, or a regular two-tube fluorescent fixture with one cool tube and one warm tube.
Water indoor zinnias whenever the top inch (2.5 cm.) of soil feels dry to the touch. Be careful not to overwater, and never let the pot stand in water. Fertilize potted flowers every other week, using a dilute solution of a water-soluble fertilizer.
Zinnias as houseplants will last longer if you deadhead blooms as soon as they wilt. Use shears or clippers, or just pinch the blooms with your fingernails.
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FAQs
Be careful not to overwater, and never let the pot stand in water. Fertilize potted flowers every other week, using a dilute solution of a water-soluble fertilizer. Zinnias as houseplants will last longer if you deadhead blooms as soon as they wilt.
Do zinnias do better in pots or in the ground? ›
Zinnias are versatile and adaptable plants that thrive in containers just as well as they do in traditional garden beds. If you just sighed in relief, I can relate because I did too when I heard this fabulous news!
Will zinnias come back every year? ›
Do zinnias come back every year? No, they don't. Zinnias are annuals, meaning you will have to replant every spring. During the growing season, make sure you are pruning and deadheading old blooms to keep your plant from going to seed.
How often should I water zinnias in pots? ›
Zinnias require regular watering but do not overwater as they can tolerate dryer soil better than overly wet soil and too much water can cause fungal diseases. Only water when the top 1-2 inches of soil are dry and try to water the base of the plant and not the foliage when possible.
Do zinnias like sun or shade? ›
Light: Zinnias grow and flower best in full sun. They can flower in part shade, especially in warmer climates with afternoon shade, but they may be more susceptible to disease and have fewer flowers. Soil: Zinnias grow best on fertile, well-drained soils high in organic matter.
What do overwatered zinnias look like? ›
Overwatering is like giving your plants an all-you-can-drink buffet when they're not thirsty. This excess moisture can lead to root rot and weakened stems, making your zinnias slump like a deflated balloon.
How do you keep potted zinnias blooming? ›
Deadhead your zinnias as the blooms fade to promote more flower production. Trim each dead flower off at the stem, which will also stimulate more growth to keep the plant bushy and full. Make sure the foliage stays dry and has good air circulation to prevent fungal infections like powdery mildew.
Should I deadhead zinnias? ›
Zinnias are deadheaded to encourage plants to produce more flowers. Zinnias are annual flowers—their life goal is to reproduce. At the beginning of the season, they focus their energy on growth and blooming to attract pollinators like butterflies and bees.
Can I just scatter zinnia seeds? ›
Even the planting process is easy. I put down fresh mulch, then sprinkle the Zinnia seeds where I want them. I don't worry about spacing or anything, I just scatter them. When the seeds are down, I sprinkle just a little more mulch over the area for cover.
Do zinnias multiply? ›
If zinnias are allowed to flower and set seed and the seeds drop to the soil, then there is a good chance that the seeds will germinate and grow the following spring. There is no guarantee that it will happen, but this is one of the main reasons why these flowers are loved by so many gardeners.
You'll probably need a high-intensity grow light, or a regular two-tube fluorescent fixture with one cool tube and one warm tube. Water indoor zinnias whenever the top inch (2.5 cm.) of soil feels dry to the touch. Be careful not to overwater, and never let the pot stand in water.
Why are my potted zinnias dying? ›
Lack of Water. One of the more obvious reasons zinnias turn brown is due to not getting enough water. Even though zinnias do not require a lot of water, there is a point where they do need some water. If you've been experiencing drought conditions and your zinnias are starting to die, it's likely due to a lack of water ...
Is it better to start zinnias indoors or outdoors? ›
Zinnias may be started indoors or directly in the garden. If you have good conditions for growing them indoors such as plant lights, a heat mat for germination, then you can get a head start by starting them indoors.
Can zinnias grow in pots? ›
Yes, zinnias will grow in pots, and there are some compact varieties that look fantastic all summer long.
Are zinnias toxic to dogs? ›
Zinnias are generally not toxic to dogs, but they can cause mild stomach upset. Here's what to do: Remove any plant material from your dog's mouth, if possible. Offer water to help wash down any ingested parts and to keep your dog hydrated.
Do zinnias like to be crowded? ›
Do zinnias like to be crowded? Zinnias generally prefer to have some space between plants to thrive and produce their best blooms. When spacing zinnia plants, aim for approximately 15 to 30 centimeters apart.
How long do zinnias last in the ground? ›
One of the easiest annuals to grow, zinnia flowers bring an explosion of color wherever they go. The show lasts from late spring until the first frost in fall.
How do you grow the best zinnias? ›
Plant zinnias in rich soil amended with compost and organic fertilizer. Choose well-draining soil with a pH between 6.0 and 7.0. Amend the soil with compost or aged manure to improve fertility and drainage if needed. Zinnias don't need supplemental fertilizer throughout the season.
