A love ‘em or hate ‘em relationship
We love them for their mounding beauty in pots. They can be a showpiece on their own or a magnificent addition to a large combination planter.
We hate them for their leggy, sticky habit as they age, and their old-growth gets brown, making a mess of our hands if we try to prune them without gloves.
However, growers have developed new types of Petunias, said to be self-deadheading and don’t have this sticky problem.
If you are old school in your favorites of Petunias (like I am), there are ways to prevent the plant’s icky, sticky nature. (See below under Care)
The Long Season for Petunias in Desert Pots
Petunias handle the desert’s cold winters well.
Petunias are a “Shoulder Season” annual along with Snapdragons, Alyssum, and Dianthus which means they also can be planted in the late summer heat that stretches into autumn’s months where the thermometer seems to stall out in the upper 80’s and ’90s.
Planted in the fall or winter months, Petunias will last well into spring and some homeowners have been able to keep them going through the summer in the right conditions.
Note: Petunias will reduce or stop flower production when it is cold. They will start strutting their stuff with brilliant color as soon as it warms up again.
The Genus of Petunias
Petunia is a genus in the family Solanaceae and one of about 20 species. We are most familiar with “grandifloras” with the largest flowers and spreading varieties such as the newer “wave” petunias.
Some botanists place the plants of the genus Calibrachoa or Million Bells in with Petunia but many disagree with this. They certainly do have a similar shape in their flowers. Still, Million Bells are much smaller and not as strong in the desert’s challenging climate.
Why I like Petunias in our Desert Pots
While I say this with a little hesitation, I do love Petunias in pots. There are so many colors and varieties. More hybrids come out each year, tantalizing our visual senses and tempting us to choose one of each for our garden. However, they do have that sticky growth factor, which sometimes I’d rather not deal with.
But getting back to the colors! That will usually cause me to scoop them up! You have single color varieties and multiple colors washing into each other. Double varieties remind me of old-fashioned roses!
Using Petunias in Pots
You will often find some Petunias in nurseries all year long. The best times to buy them are September through April. It would be nice to plant them after we get out of the 100’s at the end of summer and before it reaches the 90’s in the spring, giving them their best chance of a strong growth start.
If you plant Petunias during any of the hot periods of the year, plant them in the afternoon shade.
As with most annuals, Petunias do well in a rich, peat-based planting mix that gives them a consistently moist medium to spread their roots. Use my regular fertilizer instructions and planting techniques. If the plant’s root ball is dry, water it thoroughly before planting.
Dig a deep hole in your container’s soil, but not so deep you will bury the plant. Make sure that you do not cover the roots more than they were in their nursery can. Space them two to three inches apart to fill your pots from day one. They will quickly grow filling the empty spaces! Pack the soil around them and water well after planting.
How to Avoid Sticky Branches!
Deadhead weekly down the stem to a junction point or where you see new growth. Do not only remove the flower petals. You want to deadhead down the stem to the next growth.
As they really take off, prune long branches back to the inside of the plant to further their mounding habit. This way you will also be limiting that sticky, icky phase as you don’t keep the older, long branches on the plant.
Petunias do best in consistently moist conditions and supplement their nutrients with a water-soluble fertilizer every two weeks. Jet-blast and deadhead as you would any flowering plant.
Cover your Petunias as you would any tender plants when the forecast predicts temperatures at 32° or lower. Remember to adapt your plans depending on your temperature variations based on your location, elevation, and microclimates.
Post pictures of your Petunias in our Getting Potted in the Desert Facebook Group!