Marianne Binetti

Marianne Binetti: Paint your garden with brilliant petunias

Get thee to a nursery this second week of May because you now have the green light to fill window boxes, plant up porch pots and turn your patio into a blooming wonderland of color.

Combining colors in a container garden is a lot like painting a picture, and many of our most famous artists have been gardeners as well. I’ll be speaking this week about Art and Artists in the garden (check for details), but these three types of petunias will help you paint your own summer color with success:

Superbells Calibrachoa hybrids: Compacts for small spaces.

These bright bloomers look like mini petunias, only they are much better behaved. In our climate the Superbells resist rain and wind damage and fill up a container with compact and tidy blooms in enticing bicolor combinations. Mix the Superbells with spiky plants and trailing plants or pot up a bunch together for a massive display. If you have a small space, these make a big impression.

Coralberry Punch Calibrachoa is a bicolor that blooms orange with a dark eye and looks great in a terra-cotta pot or next to a brick wall or walkway. You don’t need to remove the spent blossoms — just feed and water for repeating blooms. Plant with orange and lime green coleus and purple sweet potato vine for a trio with a tropical punch.

Supertunia Petunia Hybrids: Mid-size blooms and medium size plants

Bicolor blooms make the Supertunia hybrids perfect for combining with foliage plants or using as specimens. The show stopper that started the sensation was a purple-and-lime-green petunia called “Pretty Much Picasso,” and this year you can find the Supertunia “Picasso in Pink” with the same lime green edging around the petals but with a bright pink center. The vivid colors mean you can turn up the color volume by adding these around an evergreen shrub or as a cascade from a mixed basket. Supertunias are super easy to grow in sun or semishade.

Wave Petunias: Oceans of color from groundcover petunias that will swamp the garden with a sea of blooms.

If you have a large space to fill, look for the Wave petunias that will spread out to three feet wide and one foot tall. The Wave petunias come in solid shades of white, pink and purple, and you can mix and match to make stripes or drifts of color. Like all petunias, the Wave petunias do best in full sun in soil that drains well but can be kept moist during the dry months of August and September. You don’t need to deadhead or prune back these spreading petunias, but you do need to give them room to grow.

Tips for growing petunias: These are annual plants, which mean they live for just one summer but will bloom until the first hard frost, usually in October. Petunias are heat-and sun-lovers but will adapt to half day of sun with fewer blooms. Like most annuals, petunias need plenty of fertilizer to keep pumping out the flowers, and the soil should be kept just barely moist. Work some slow release plant food into the soil at planting time, and then feed every two to three weeks with a liquid plant food as well. If your petunias grow too long and leggy, you can cut them back to just a few pairs of leaves and fertilize with a liquid plant food. In a couple of weeks, they’ll be covered with more blooms on a more compact plant. In general, the bigger the bloom, the larger the plant and the more space the petunia will need.

Garden gossip on petunias — the double flowering petunia varieties look great in the greenhouse, but they do not hold up well in rainy weather. Unless you have a protected spot to grow them out of the rain, you’ll be disappointed.