Petunia: sowing, planting, cultivation and care

The Petunia (Petunia x) is a perennial cultivated as an annual which belongs to the family of Solanaceae. Native to Brazil, it grows and flowers very well in our latitudes. Petunia is one of the essential plants for flowering beds, borders, terraces, windowsills and balconies. Its abundant flowering, which comes in purple, white, red, pink, black, plain or variegated, works wonders from May until frost. The Petunia is unparalleled in transforming any outdoor space and it is a real pleasure to grow different varieties because these plants do not pose any particular difficulty. Here is how to sow, plant and maintain your petunias.

Sow the Petunia

Seedlings allow you to get your own petunia plants rather than buying them. You just need to get a bag of petunia seeds in one color or in a mixture to give birth to many plants a few weeks later. But let’s not hide it, petunia seedlings are rather to be reserved for gardeners who already have a great experience in the field.

It is between February and March that you can start sowing your petunias, but the ambient temperature must be around 20 ° C, that there is no draft and that the light is generous. If it is still too cold, the seedlings must be placed sheltered either in a bright room or under a frame or in a tight.

We install the seeds on a potting soil then they are covered with a thin layer of fine sand. As for the containers, they can be biodegradable egg cartons, wooden crates or polystyrene boxes. As soon as the young seedlings measure a few centimeters in height, they must be transplanted into individual cups where they will continue to gain in force. The buckets are kept under cover at the start then can be taken out at the sunniest hours of the day to be brought in at night.

Plant the Petunia

Buying petunias in pots from a garden center allows you to skip the sowing stage. By opting for this solution, it only takes an hour to flower a balcony, a terrace or a bed, since you only have to transplant each plant as soon as you buy it.

We multiply the types of containers, planters, pots, basins, pots. Growing in the ground is also possible because the Petunia is ideal for flowering a rock garden or to bring a decorative note to the foot of an old wall. Note that if we want to obtain waterfalls of flowers, we install the plants in suspensions and we opt for Surfinia (Petunia x ‘Surfinia’). This is a Drooping hybrid petunia.

The period of planting the Petunia in place begins in may. Planting these perennials does not require any special knowledge.

  • For a plantation pot, at the bottom of the container – which must absolutely be pierced – place a drainage layer about 5 cm thick like clay balls or gravel,
  • Then fill the pot or the planter with a mixture of garden soil and potting soil for flowering plants,
  • Dig a hole,
  • Take the plant out of the bucket after leaving it to soak for about 15 to 20 minutes in a container filled with water,
  • Place the plant in the hole,
  • Recap by compacting the substrate around the foot without damaging it,
  • Water copiously.

For a petunia culture in the ground, we recommend counting at least 5 to 6 plants per square meter in order to obtain an extremely colorful flower carpet (single tone or multicolored). The result is a surprisingly beautiful ground cover and the visual effect is truly breathtaking for many months to come.

Growing Petunia

The Petunia is undemanding. It is therefore easy to cultivate provided it can benefit from a perfectly draining soil because it don’t like having roots in water.

In addition, he likes to be installed in a moderately humuse, furniture and slight. He appreciates the sunny situations, sheltered from the wind and drafts. During a heat wave or in regions with a hot climate, it is preferable to install your petunias in a semi-shaded area. Note that to flower well, petunias and surfinias must be able to benefit from 6 good hours of sunshine per day in the morning and late afternoon.

Once the first frosts appear, petunia season draws to a close as this non-hardy plant not resistant to negative temperatures.

Caring for the Petunia

Regarding the maintenance of the Petunia, it comes down to the following actions.


We must be able to offer a sufficient freshness to its petunias by watering very regularly so that the substrate is never dry. If they are grown in planters, water must be watered more frequently than in the ground, especially in periods of high heat, without drowning the roots so as not to suffocate them. You should therefore not overwater and during periods of heavy and frequent rains, the watering can can remain in the shed for a few days.


To enjoy a abundant flowering from spring to autumn, it is necessary to bringliquid fertilizer to dilute for flowering plants. Particularly rich in potash, this fertilizer should be added to the irrigation water approximately every 8 days for a guaranteed decorative effect, but it is important to always respect the dosages clearly indicated on the container. Also be careful never to distribute fertilizer to a plant if the substrate is dry.

Parasites and diseases

The petunia is very interesting because in addition to flowering abundantly and being easy to grow, it is a not very sensitive perennial. At most its tender young leaves attract slugs that we can easily move away from the flower beds by spreading a little sand on the ground.

It is also possible to see aphids that it is necessary to eliminate quickly in order to avoid a severe attack. If we have not taken the precaution of installing ladybird larvae on plants, we must resort to a organic anti-phlegm preferably so as not to harm the environment. A mixture of black soap and Marseille soap to be diluted in hot water allows (after complete cooling) to treat effectively against these undesirable. The treatment must be carried out regularly to obtain excellent results since it can eradicate aphids.

As for the diseases to be feared, they are few due to the great resistance of Petunia. However, beware of non-draining soils in which the water stagnates. Excess water at the roots can cause them to rot and kill the plant.

Whether it is cascade, drooping, with small flowers or with double flowers, the Petunia is very appreciated because it does not require no special care apart from the regular waterings. It is still capable of flowering profusely for about 6 months. But to facilitate the production of new flowers, it is recommended to remove all those that are wilted as they wilt. This small perennial plant will thus retain its beauty.