Easy-to-grow petunias offer lots of color-mixing possibilities


April 05, 2007




When I was asked to write an article on my favorite annual, I had to think long and hard about what my favorite might be. I have been gardening for many years, starting with working with my mom in the yards at all the many houses we had moved to.


After moving, and in short order, we always had one of the nicest yards in the neighborhood, with my mom planting drifts of flowers of whatever type and variety caught her eye. I particularly remember big showy petunias lining her flowerbeds.


After many years and after some maturity, I started shopping at Texas native plant sales with my sister Mary. She is a very particular plant connoisseur, with nary a petunia or periwinkle gracing her wooded wonderland of native beauty. I hope if and when she reads this article she will forgive me, but, after much soul searching, I will have to admit my favorite annual, at least for now, is the petunia.


Petunias (petunia x hybrida) hail all the way from Tropical South America and, believe it or not, are related to the common vegetable garden potato. The petunia is in a group of annual or perennial flowering plants which number about 30 species, give or take a few. The showy petunia blooms come single or double, ruffled or fluted, with a wider variety of colors available than almost any other flower can offer. Their growth height is anywhere from 6 to 30 inches.



With a wider variety of colors than most any other plant, petunias often are two-toned, some with contrasting "stars" and others with fringed or "picoteed" margins like these burgundy petunias.



According to the book "Tough-As-Nails Flowers for the South" by Norman Winter, "The Petunia wasn't a flower that was considered tough until the mid-1990s. This changed with a group called the 'Wave' series. The 'Waves', 'Easy Waves', and 'Tidal Waves' now give the gardener a petunia that will probably bloom from spring through frost. Some are showing remarkable cold tolerance, allowing them to either bloom during the fall and winter or return in the spring."


The wild petunia (petunia integrifolia), is a species of petunia that was chosen as a Texas Superstar since it is cold-tolerant, takes heat and is disease-resistant. It has smaller, violet-colored blooms and makes an excellent ground cover or container plant. Many of the newer petunia varieties have flowers that are also more resistant to heavy rain and wind damage than previous varieties were prone to.


Petunias prefer full sun, but will tolerate some shading from the hottest afternoon sun, and have average water needs. In order to keep them growing strong and constantly blooming, feed with light applications of fertilizer every four to six weeks.


Pinching off the faded flowers prolongs bloom time and petunias can be cut back after the first flush of blooms to encourage additional flowering. Many of the older varieties will finish their growth and blooming with the arrival of the hot summer weather, but new types will hold up a lot longer. Petunias really prefer the spring and late summer/fall time of year.


It is always wise to maintain a hearty layer of mulch to conserve soil moisture and keep soil temperatures cooler. This holds true with whatever flower varieties you are growing.


Petunias can be propagated from seeds or by cuttings; however, you can receive a major hand slap from the Plant Fairy if you attempt to propagate cuttings from patented varieties. Sometimes it is just wiser to purchase your babies from your local plant-selling establishment.


If you do decide to propagate from seed, sowing can take place January to March. Petunias will germinate with a minimum temperature of 70 degrees. The seeds should not be covered with soil, and they should be kept in the light for the best germination success. Seedlings will generally appear within two weeks or so. Petunias are also generally pest-free with the occasional aphid or snail attack; however, they seem to grow so fast that these pests usually don't do too much damage.


And as a special bonus, petunias are reported not to be on the favorite dining menus for our friend the deer.



When looking for complementary color combinations and companion plants for petunias, remember the color wheel with opposite colors. Purple petunias with orange snapdragons can really showcase a colorful planting.




Petunias offer a myriad of landscape uses. They can be used in mass plantings of single colors or in pots or hanging baskets. Avoid the common mistake of planting them in a single row along the front of your flowerbed like little soldiers. They will put on a much more attractive show if planted in a staggered row to allow them to fill in the area. Growing petunias in containers can be especially fun. Containers can be moved around to suit your outdoor decorating needs and can even be moved into a flowerbed to add an extra shot of color.


Many two-toned color types are available, some with contrasting "stars" and others with fringed or "picoteed" margins of different colors. When looking for complementary color combinations and companion plants for your petunias, remember your color wheel from school and that opposite colors do attract.


Purple petunias with gold lantana or orange snapdragons or blue petunias with orange or gold marigolds, pink petunias with blue plumbago or yellow petunias with purple trailing lantana; the combinations are seemingly endless. One of my most surprising color "accidents" happened last year when a particularly hot pink spreading petunia decided to wind its way around my blue agave plant; to me, a very striking and pretty color combination.


I am sure that after reading this article my sister Mary will forgive me, I think she loves me just that much. But I know my Mom will be proud of what she taught us.


The Gardeners' Dirt is written by members of the Victoria County Master Gardener Association, an educational outreach of Texas Cooperative Extension-Victoria County. Mail your questions in care of the Advocate, P.O. Box 1518, Victoria, Texas 77901; or vcmga@vicad.com, or comment on this column at www.VictoriaAdvocate.com.