Sensation mix Cosmos Seeds produce tall single-flowered plants for back of borders, bi coloured and single coloured blooms for many months in the summer. The fern like foliage makes this plant an amazing back of  border feature and an amazing cut flower. Cosmos plants flower all through the summer into October. Grows to about 1 metre tall. And with 75 seeds you can get a great big patch of cosmos in the garden.

Also see our other cosmos varieties:

- Cosmos Fizzy Mixed seeds

- Cosmos Fizzy Rose Picotee seeds

- Cosmos Breeders choice mix seeds

- Cosmos Candyfloss mix seeds

How to grow cosmos flowers from seeds?

Are you interested in growing Cosmos flowers? Did you know that there are at least ten species of this plant? They all have beautiful vivid colours, with head-shaped inflorescences characteristic of the Asteraceae family. The simplest flowers look like miniature sunflowers or dahlias but come in different colours, ranging from pinks and reds to oranges. Cosmos plant has a long flowering season from May to October, which makes them an ideal garden flower choice.

A brief history of growing Cosmos

The plant is more commonly known as Annual Cosmos or Mexican aster. It grows natively in the Central American region but is widespread throughout South America and parts of Africa. Knowing this, it is easy to conclude that the Cosmos plant enjoys warm areas with constant exposure to the sun. To create a perfect growing environment, you must mimic these conditions as closely as possible. Otherwise, you may not be able to experience the lovely blooms it produces.

You can find this sun-loving Cosmos bipinnatus (Latin name) near roads, waste places, and recently in many parks where it attracts birds and butterflies. It requires moderate care and can tolerate temperatures from 0° to 42 °C (32° to 109° Fahrenheit. It is known as a plant that symbolises persistent happiness, order and harmony among people. 

But how do you succeed in growing Cosmos on your first try? In the following, we offer planting and maintenance instructions to ensure your plant’s full growth. 

Planting process 

When planting Cosmos plants, it's essential to consider various factors, including planting season, location and choosing a suitable soil mix.

Timing 

Cosmos seeds are frost-sensitive. Knowing this, you are right to assume that you should not be growing Cosmos during the winter period. Instead, start planting as soon as the last possibility for frost expires, ideally in the period of spring or early summer (from April to May). Wait for temperatures to climb to 10°C.

Location 

You should start the whole process indoors right when the growing season starts. However, you should later transplant the seedlings outdoors once the weather is suitable, as this plant enjoys thriving outside.

Soil mix

The first thing to remember about growing Cosmos flower is that this plant requires well-draining soil. Good drainage and air circulation are essential. To ensure that, choose seed-starting mix or peat moss soil. Add perlite or vermiculite to the soil in a 1:1 ratio. Leave some room to supplement with specific retention and aeration improvers such as coconut coir. For a better initial feed, add worm casting. 

Tip: There is one magical ingredient you can use, which is also cheap- egg shells. Adding this to the potting soil mix will ensure your plant gets enough calcium, which is essential for its growth.

Perfect Pot for Cosmos Plants

To begin with, you can use small pots and then transplant your plants into larger ones. You can even use paper self-degrading pots that you will later transfer to a larger pot or directly into your garden. The pot for an already grown plant should be a minimum of 12 inches wide (diameter)  and at least 2/3 the size of the plant. Look for suitable materials, such as terracotta or ceramics. Do not plant in a large pot right from the start. This will make the plant unable to develop roots and use its maximum potential. 

Seed selection

After you have selected the right pot, it is time to choose seeds. Note that you should adjust the selection to the area you live in. If in doubt, choose one of these two species: Cosmos bipinnatus or Cosmos sulphureus. They are the most easily adaptable and drought tolerant. Choose cosmos seeds from a reputable seed supplier. To ensure that, read a review or visit our shop, which offers you enough information. Finally, focus on viability. Look for the phrase “sell by/ packaged by” and the date indicated until when those seeds are good to use. Do a simple home test to check whether the seeds you have bought are viable. Wrap the seed in a wet napkin and leave it in a dark place. If it sprouts in 3-4 days, it is still fresh. Ask for a small starter pot and choose that one.

Growing Cosmos from Seed

After preparing the soil and choosing a sunny location with good draining conditions, make a small hole and scatter the seeds evenly over the soil surface. Lightly press them into the soil, but do not bury them too deep. After that, water a little or moisten with a small amount of water. Avoid over-watering. Keep the soil moist until the seed germinates. It can take around 7-14 days. If the seedlings are too close together, thin them out to allow proper growth spacing. After small stems appear and grow, you have probably already welcomed summer. The last frost date is away, so you can repot the plant outside.

Maintenance of care

It is recommended to water every 7-14 days. Initially, the soil may be moist, so be more careful with overwatering. Try to maintain a humidity level of 40-60%. Therefore, it is best to first keep it inside or in a greenhouse.

Do regular checks. Also, mulch around the plant to suppress weeds. Shelter the plant from winter frost if winter is already on the threshold. After the one-month adaptation, consider a liquid fertiliser. Be informed about the amount and follow the instructions for preparing the solution.

Preserving Future Blooms

The Cosmos plant is a herbaceous annual plant. If you want to preserve it for next year, you can try propagating it from cutting or water propagation. To do that, you should choose a healthy 4-6 inches long stem and cut it off. Remove lower leaves and put the cutting in well-drained soil. Maintain good humidity and indirect sun exposure. Learn more about rooting hormones if you want to speed up the process.Another more practical option is water propagation, which is more time consuming than growing from seeds. Put a similar cutting in the water (room temperature). Place it next to the window and wait for the root to appear. Then, plant in the pot.

Final thoughts

Hopefully, these tips on growing Cosmos from will make your venture fruitful and enjoyable. Follow the instructions we have given you and enjoy planting your cosmos seeds in your gardening.