Petunias are a classic warm season annual that can make a space bright and lively. They can be purchased in the spring and can bloom through the summer until frost if managed properly. Also, they have a fragrant scent, but best of all, they are easy to grow in both a garden or containers.

As there are hundreds of petunia varieties, some petunias are more suited for some environments than others. The two most broad categories are seeded and vegetative varieties. Seeded varieties tend to be the cheapest because there is less that goes into getting them on the self than their counterparts. However, they often don’t have the best growing bait and must be deadheaded. Understand that the plant’s main purpose is to produce viable seed. Once it has bloomed there is no reason for it to continue blooming. By deadheading, it can be tricked into blooming again. To do this, once a bloom starts to shrivel up and turn blown, pluck not only the flower off, but the small bud structure behind it. This is called the ovary and where the seed will be produced. 

The other category of petunias are vegetative varieties. These are improved varieties that have been bred to continuously bloom. These varieties must be vegetatively propagated to make sure the new plants have the same characteristics of the mother plant. These varieties tend to be more expensive, but oftentimes because of their growth habit and continuing blooming you can get away with planting less plants to get the same amount of blooms. Because these plants do not have a goal of going to seed, they are considered ‘self cleaning’ which means deadheading is optional. They can further be broken down into categories based on flower size and growth habit. Grandiflora have the largest flowers. Multiflora have greater numbers of somewhat smaller flowers. Mulliflora are miniature with an even smaller plant and flower size. Finally, there are ‘spreading’ types. These are fast growers that can fill large spaces.

No matter the type of petunia you choose, there are a few things to consider when planting. Make sure to place plants where they get at least 6 hours of sunlight per day. If you have a shadier area, they will not have as many blooms. For these shady areas, impatiens, coleus, or begonias may be better options. Make sure you have good drainage. For sandy areas with low water holding capacity, the addition of organic matter will be important. Peat moss, compost , or manure are great options. 

Petunias thrive with consistent, even watering. They are a bit dramatic when they get too dry by wilting, but will usually perk back up when watered. If kept too wet, they can have disease issues. It’s best to water so that the leaves don’t get wet. However, this is not always practical so make sure that when you water from overhead that you do it early enough that the leaves dry before sunset. Drip irrigation can be a useful investment. During the hottest days of summer, you may have to water twice especially if you are growing in containers. Water first thing in the morning and again in the afternoon.

Like many annuals, petunias are hungry plants. They do best when fertilized once or even twice a week. Select a complete water soluble fertilizer. Replace two clear water waterings with waterings with fertilizer.

The last management practice that will keep your petunias beautiful all summer long is pruning. If your plants get too leggy or are too large for your liking, you can always cut them back. This will encourage new growth and flowering. Prune long stems back to a bud or a node, taking away about 20% of the size. Pruning can be done all at once or throughout the growing season. If done all at once, plants will need some time to put blooms back on. Depending on how much is cut off, they may take a week or two to put new blooms back on. If you don’t want to sacrifice color, you can prune a little bit at a time. This is more time consuming, but at least your plant won’t be bald.

With proper care, your petunias will bloom well into fall, keeping that bright and lively color lasting all season long. For more information about landscape or container gardening, contact N.C. Cooperative Extension, Richmond County Center at (910) 997-8255. In addition, follow us on Facebook or visit our website for upcoming events and up to date information.