Petchoa-“the all-season” petunia?

July 22, 2021

Do You Wish Petunias Would Last Longer In The Summer?

Petchoa is an “all-season” petunia. We, gardeners, love Petunias; we are happy with the much newer Calibrachoa, which looks like loads of small petunias on a colorful mounding and trailing plant. The Calibrachoa was released in 1992. The flower is similar to Petunia, and the plant has better resistance to hot, humid summers than the Petunia. So it has a place in our gardens.

Calibrachoa was actually discovered in South America in the 19th century. However unlike the petunia which was universally loved, almost immediately, the calibrachoa was for many years ignored as hard to grow. Later we discovered its unique and valuable ability to be bred in extraordinary colors and the rest is history,

Use calibrachoa for its ability to last longer than petunias into the heat of summer and the unique colors. It is called “million bells” for the very large number of small, but petunia-like blooms.

So why do we need another very similar plant, a recently bred hybrid? It is a cross between a Petunia and a Calibrachoa. So what does it bring us?

Here’s Why!

Petchoa (pet-KOA-uh) has large flowers, as wide as the Petunia and almost as long. It withstands heat, wind, and rain better than either of its parents. It is well branching (means no pinching), and the foliage is not sticky (less deadheading). So, because it accepts both cooler spring and fall temperatures and late summer heat and humidity, it should outperform either parent! In addition, it can minimize disease as well as pH issues better than either parent. (The Petchoa tolerates high pH levels the best.)

In addition, petchoa tolerates rain better than other petunia plants. Therefore, the blooms will remain open in light rain and withstand bad weather the best.

What To Call The Plant

Petchoa is the genus and you will find about 20 cultivars. The name comes from the plant’s two parents. PETunia (the natural parent) and calibraCHOA-second parent. Say it as if it is spelled PetKOAa, and they will know what you want in the garden center. As a popular new plant, you will find it in season in the big box stores and in local garden centers too.

In Petunias, Color Is Important-What Colors Can Petchoa Give Us?

As a new hybrid, the Petchoa has two series of cultivars, each with color choices. I found early testing of this plant in public botanical gardens in 2010, with branded varieties about 2013. So that is about how long it has been with us. New cultivars are produced by breeders each year. I have a brief list here, I will continue to update it, but you should not consider it perfect. My lists are designed to help you know what you should reasonably expect at the garden center. There are always regional differences.

  • Calitunia series-Calitunia Purple, Fuschia trumpet-shaped flowers with deep purple centers, also in pink. Calitunia is the trade name for the first petchoa, developed by the breeder, Danzinger.
  • SuperCal series-Large vibrant flowers, from spring to first hard frost. It survives late spring frosts, rain, and heat. New colors include , Bordeaux, Caramel Yellow, Premium Cinnamon, Premium French Vanilla, Premium Pink. The SuperCal series is the trade name for the petchoa developed by the breeder Sakata.
  • You can now expect about 20 different colors including blue, and multicolors. The calibrachoa parent contributed the larger color choices. Look for some beautiful offerings with colored veins.

Petchoa Withstands Rain And Some Surprise Freezing

When a rainstorm is not extreme, the Petchoa flower remains open. The Petunia closes up and is more easily damaged in the rain. The Petchoa has a reasonable ability to withstand the surprise spring frost. Always plant the spring/summer flowering annuals after the date of the last recorded frost. This is nice protection, however, if you make a mistake! Here is a link to NOAA’s map showing the last spring frost history.

Petchoa Is Compact And Why That Is Important

Compact, means that the leaf internodes are close together. This creates an especially dense display of flowers.

Improving On Petunias In The Summer Garden

We all love the Petunia in the spring garden and, depending on your hardiness zone; you may have good luck through much of the summer. We have gardened in several locations, and New England expected the Petunia to last the summer (except for thunderstorms and hail). In more southern areas, late summer was harder.

Today we garden in South Florida, and the Petunia is something we have learned to love in the winter. So we can have a long season of pleasure with them. In spring, they are gone. Early in April, we tore them out, completely spent! There are Calibrachoa, in hanging baskets, so far, so good. In our first year growing them, calibrachoa made beautiful winter baskets and lasted until about mid-summer.

So we are always interested in planting ideas for mid to late summer-our hardest period. (See the series “This Month In The South Florida Garden for how things change here and how to cope.)

Pollinators And Other Wildlife

Pollinators-The various trumpet-shaped plants should attract butterflies and hummingbirds. They come to the Petunias and today are buzzing the Calibrachoa. I find that rabbits favor the tender Petunias and have learned that containers are my salvation.

There are debates about deer, but my experience is that they will eat the Petunias if they can reach them. On the other hand, I see some reports that the Calibrachoa are more bitter and less attractive. The safe rule of thumb for rabbits and deer is that they will surprise you with what they will eat if they are hungry.

How We Can Use Petchoa

The Petchoa is as Petunia-like a plant as I have seen. More so than the Calibrachoa, although the distinction is mainly that the Calibrachoa has a smaller and very similar blossom. The trailing behavior of all three plants is very similar.

Is the Calibrachoa a Petunia? Well, where is your garden? In the US, we have decided that they are two different genera in the same family, the Solanaceae (Nightshade). The reason for separating the genera of the two plants? In 1990 scientists discovered that the Petunia had 14 chromosomes and the Calibrachoa had 18.

In the UK, the Royal Horticultural Society keeps them in the same genus. So it does depend on where your garden is.

What about the Petchoa? It is called XPetchoa, and it is classified as its own Genus. So three similar plants, each with its own features and all in the same family but each a separate Genus. The Petchoa among plant breeders is considered a “Milestone” accomplishment and is a sterile plant and produces no seeds.


Petchoa, like the other two, has a graceful and colorful trailing habit. As such, it is pleasing in these applications.

  • Containers, small and large
  • Hanging baskets
  • Window boxes
  • ground cover and lowest level of garden beds

Pests And Diseases

The important news here is that the petchoa is far more resistant to powdery mildew.

Pests are those which attack the parent plants. These are Aphids, Leaf Miner, and Thrips. To minimize risk, observe the plants regularly; if you see tiny bodies, damaged leaves, or sticky substances, remove the damaged foliage. Wash with water or insecticidal soap. Maintain airflow between the plants.

Disease, Plants are attacked by Botrytis, a fungus that can attack all plants. I can find no plants which are resistant to Botrytis. Humidity creates a favorable environment for the disease. The best procedure is to control the environment. It helps to maintain sterile tools and equipment, to ensure airflow and sun. Some Fungicides are available.

Powdery Mildew is a problem of petunias in wet or humid weather and where drainage is insufficient. Petchoa is resistant to the disease, and that is a considerable benefit to look for.


This is a new alternative for our color gardens. It has strong roots and large flowers from the Petunia parent. From the Calibrachoa, it gets vibrant colors that stand up to harsh conditions.


Petchoa, like petunias, will attract butterflies and hummingbirds.

Companion Plants

Any strong growing plants which enjoy the same conditions can be successfully grown with the Petchoa. Consider smaller tropicals such as banana, canna lily, or caladium. Also, use any of the popular summer annuals that require full or near the full sun and moist soil.

Petchoa Breeders-What To Look For When Buying Plants

The first petchoa were created by the plant breeder Danzinger. Their plan”Calitunia” I can find two varieties, Cakutunis Pink and Purple.

The next major developments from the breeder Sakata and their trade name is “SuperCal” and there are 11 varieties.

There are links to discussions on both types below.

How To Tell The Difference Among the Flowers


The petchoa bloom is as wide as the petunia but slightly shorter. The appearance is a bit more ruffled than the petunia parent. It takes its very vivid color from the calibrachoa parent. The petchoa does not produce seeds. This causes the blooms to stay on the plant longer.

The foliage of both the petchoa and the calibrachoa are not sticky, this means that the blossoms fall cleanly from the plant. The petchoa tolerates a higher (more alkaline) pH than the calibrachoa.

The petchoa shares with the petunia, a strong root system, this makes them better than the calibrachoa at taking up nutrition.


Calibrachoa looks like a clearly smaller flower than the petunia. It shares the mounding shape and training habits. Calibrachoa is resistant to tomato (or geranium) budworms and they are famous for their wide range of colors. Why choose one over the other? Calibrachoa requires superior drainage, if you cannot provide that, petchoa is the better choice.


This plant has the largest flowers, in the Grandiflora variety, the blooms are 4″ across. If you can protect them from the rain and you think bigger is better…

My Garden Reference Page


Annual Bedding Plants



Super Cal Petunia-this is the plant breeder’s page.

Calitunia-this is a report on their early development.

Petchoa infographic