If you are looking for annuals that bloom in summer right through early or mid-fall, Cosmos is a perfect choice. These easy-to-maintain plants grow tall and slender and have daisy-like flowers that are quick to bloom. The flowers to feet or inch ratio of this plant surpass most plants in the same category, making it the number one choice for any landscape or balcony garden.
In this article, we will go through intricate details about growing and caring for Cosmos flowers through questions frequently asked by balcony gardeners all over the United States.
What is a Cosmos flower and can I grow it?
Cosmos are daisy-like flowers native to Mexico. The name is derived from the Greek word “kosmos”, which means “beautiful.” They are a member of the aster family, and have easy care and maintain nature.
These plants are generally sold in Spring, but can also be grown easily from the seeds. These seeds can either be purchased online or at local nurseries along with other planting essentials.
While planting Cosmos be sure to leave them in a spot that receives a lot of sunlight. If you live in a region that is too hot, provide shade in the afternoon to shield them from the scorching heat.
As these plants are slender, they cannot stand strong winds, to protect them from falling over secure them with a sling. This can be done by looping a string around the plant and adding a stick or bamboo for support.
Cosmos plants are known to be low on maintenance and hence the quality of soil doesn’t matter much but that being said pay attention to the amount of water it receives.
Cosmos prefer soil that is not too rich, this is because rich soil will encourage foliage but at the cost of bloom.
They have a reputation of being draught plants when mature but need a fair amount of moisture while growing. The amount of water they receive also impacts the quality and quantity of flowers that the plant produces.
Growing and caring for cosmos flowers is not so difficult.
- 12 Best Plants That Grow in Small Pots
Can cosmos grow in pots?
Cosmos are perfect additions to balcony gardens as they grow as well in pots as in the ground. These plants come in about 20 variants and most of them grow to about 6 feet in height.
To adapt them to a balcony garden you can either prune them regularly or opt for dwarf species or compact cultivars.
We suggest the Cosmos Sulphureus and Cosmos Bipinnatus as they are best suited for containers.
The Cosmos Sulphureus are available in shades of orange, yellow and red, while the pink and rose tones of Cosmos Bipinnatus are popular.
When should cosmos seeds be sown?
To make optimum use of the blooming season it is best to sow cosmos seeds in March or April. Because these are to be planted in your balcony garden you can easily sow them through spring and early summer as well.
Alternatively, you could plant them indoors and let them germinate and then transfer them to pots on your balcony after they grow a little.
How to sow cosmos seeds?
To grow well sow seeds of the cosmos plant in a tray filled with compost. This can be either be homemade or store-bought, either way, the plants will be able to use the nutrients to grow well. While sowing the seeds remember that they need to be planted about 3mm deep.
You can then cover the tray with glass or plastic covering and leave it in a warm place for about a week.
After a week goes by you will be able to see green shoots all over, this marks the time to remove the covering and let the plants grow to about 3 to 4 inches. When they are big and strong enough, transfer them to pots on the balcony.
You can plant about 2 to 3 plants in a single pot as they grow slender and tall. Pay extra attention to the depth of the pots as these plants like to have space to spread their roots.
This helps them retain moisture and gain the nutrients required to produce flowers.
How to ensure that the cosmos plant grows well?
Growing and caring for cosmos flowers is also depends on how you are growing the cosmos plant.
The best way to get these plants to grow and bloom to their full potential is by planting them early and giving them time to grow and mature before summer sets in. These plants require at least 7 weeks to start to bloom so time the crop well.
Furthermore, as these plants are sensitive to sunlight, they bloom well only when they can soak up the sun. secondly pinching off flowers that have passed their best encourages branching and the formation of new buds.
Deadheading is recommended more often for this plant as it lengthens the blooming period. Gardening veterans swear by doing it at least once to twice a week for best results.
Another way in which you can support the growth of this plant is by providing support to the stems as the plant grows. As we know these plants grow tall and slender and hence, they tend to be bothered by strong winds and other environmental factors.
To protect them, secure the plants with a sling and provide additional support.
Tip: Don’t worry about the slings tied around the plant stealing the show, as the plant grows it will get bushier and cover them.
How to deadhead the cosmos plant?
Deadheading is the most important factor to increase the blooming period of the cosmos plant.
To deadhead a plant, cut the flower down to the main stem between the main stem and a leaf. This will promote axillary bud formation.
In about a week a new bud will form in the place where the cut was made. While deadheading the flowers don’t need to be completely wilted, you can get rid of the ones that have just past their best.
If you have more than one plant space the deadheading through the week so that you have time to go over each plant carefully.
An important thing to remember is – The deeper u cut the more time between this flower and the next. The higher you cut the faster the new flower will grow.
If you are looking to use cosmos as cut flowers the stems will need to be longer, in such cases cut between the stem and leaf at the desired stem length.
Remember: Deadheading increases the blooming period and the time you stop deadheading it will stop producing flowers.
What are the uses of the Cosmos flower?
Traditionally the cosmos plant was used for informal planting around the house. These annuals being tall were planted on the back and front border walls.
Today they are used mostly as flowering plants that add color and complement other plants in landscapes and balcony gardens.
The taller variants can be placed around pots containing perennials such as lilies, irises, and ornamental grasses. They can also be planted in combination with other annuals like cleome, and tender perennials like cannas and dahlias.
Smaller or dwarf variants of the cosmos plant are perfect when planted closer to coffee tables or planters that can be attached to the railing. This will be for a colorful skirting to the balcony.
How do I Harvest Cosmos flowers?
Growing and caring for cosmos flowers is simple, once mature you can begin to harvest flowers from the Cosmos plant as soon as it begins to bloom.
While harvesting, pay attention to where you cut the flower as this will determine bud formation.
Ideally, you need to make a cut between the main stem and a leaf, this will help the formation of new buds which will begin to grow in about a week.
The best time to pick cosmos when using them as cut flowers is right when the petals have opened. This will give it time to open gradually and will last for longer than a week in water.
To use them simply strip off the leaves at the bottom and put them in a vase.
What insects or diseases affect the cosmos plant?
The cosmos plant is known to be one that is free from diseases and pests, making it a gardener’s favorite plant.
In rare cases, the plant may attract a few household bugs or the ones that infest other plants. They may sometimes be affected by Stem canker, Powdery mildew, Gray mould, or Aphids, but this can be managed by spraying natural insecticides on the plant.
You could also cut away the affected area and leave the plant to grow naturally.
Growing and caring for cosmos flowers will not be easy if insects or diseases affect the cosmos plant.
How do I collect cosmos seeds for next season?
When the plant is mature it will start to produce spiky-brown seed heads. Let the seed heads dry on the plant before plucking them and saving them for the next planting season.
If these are left on the plant, they will blow seeds around the balcony resulting in cosmos plants in other containers which might not be an ideal situation for the growth of other plants in your garden.
How long do seeds of the cosmos plant last?
The seeds of the cosmos plant if stored in a cool and dry place can last for about 2 to 3 years. Once you collect the seeds, dry them well and store them in an air-tight container or a glass jar.
Be sure to label the jar with the name of the plant as well as the date on which the seeds were collected.
You can also use plastic baggies with details to store seeds. This will help identify seeds that need to be planted next if you collect seeds every season.
Can cosmos be planted in fall?
Cosmos plants take about 7 weeks to grow and bloom. They are sun and heat-loving plants and find it difficult to grow in cold and frosty climates.
Hence it will be difficult to grow these plants in the fall unless they are sprouted and cared for indoors in conditioned conditions and by using a heating lamp.
Recommended cosmos variants
- ‘Picotee’ – This variant had beautiful white flowers with a crimson border around the edge. Some flowers are also flecked in crimson.
- ‘Sea Shells’ – these cosmoses are adorned with white, pink, or red tube-shaped petals.
- ‘Purity’ – Purity is a classic as it is covered with beautiful white flowers that have a spectacular appearance.
- ‘Cosmos Sonata Series’ – These when planted in combination with Bells of Ireland add a different charm to the balcony.
- ‘Chocolate’ – These cosmoses add distinction to a white campanula, dianthus, or ‘Moonshine’ achillea with their distinct color and looks.
Why is my cosmos not blooming?
Cosmos are plants that do not need extra care and attention. These plants thrive when left alone, this being said the cosmos will not bloom well if they are watered too often or if the soil is not the draining type.
Pay attention to the quality of soil while planting cosmos they like moisture but will not bloom if they are soaking wet.
An easy solution to this is adding a layer of sand or gravel to the pot. secondly, make sure that the pot has holes at the bottom so that the excess water can drain out easily.
Another reason these plants may not be able to bloom is the addition of too much compost or fertilizers. As they thrive on sunlight to bloom, if the region you live in does not have enough sunlight the plant will not be able to bloom well.
They need a minimum of 3 to 4 hours of full to partial sunlight to grow. Similarly, in hot, wet, and humid conditions these plants will struggle to grow.
You may like the following balcony garden articles:
- Easy Fruits and Vegetables To Grow In Pots
- How to Create a Phenomenal Yet Low-Maintenance Garden
- Why are my croton leaves turning yellow
- 10 Best Herbs that can grow easily in your Balcony Garden
- Build and Grow a Salad Garden on Your Balcony
- 8 Best flower plants for balcony garden
These heat-loving annuals are easy to plant and maintain in balcony gardens and hence are seen all over the country. They do not require special soil or fertilizers to grow and are known to be the most blooming plant with flowers every 4 to 6 days.
As there are many variants available opt for the dwarf ones, if you plant the variant that grows tall be sure to prune them regularly at the main stem to ensure that new branches grow lower and bushier.
All in all, this is a fun and colorful plant that will add a flowery blanket to your balcony garden. Now that you have all the information on growing and caring for cosmos flowers what are you waiting for? Go plant these beauties today. Happy gardening!
I am Elsa, love gardening. I spent lots of time with plants, flowers, it gives me lots of happiness.
I am sharing all the practical tips on how to grow various plants, flower plants, vegetables in the garden. Read more about me.