Annuals and Perennials – What’s the difference?

With the many varieties of plants for the garden available on the market today, many gardeners are often confused between the term, annuals and perennials, and which plants belong in each category.

Life-cycle is used to determine if a plant is an annual or a perennial. The life-cycle of an annual is complete, from a seedling to maturing plant that produces its seed by the end of the season, within one growing season. A perennial can be defined as a plant that has a life-cycle of more than two years. Often gardeners refer to perennials, as plants that come back year after year. Which is a good rule of thumb except for one caveat, biennial plants. Many gardeners often mistake biennials plants as perennials, because they appear to come back the next year when it is the second phase of a two-year life-cycle.

Flowering annual plants, except for a few species, typically produce flowers, all summer long. Annuals can be planted directly into the flowerbed or can be used for container gardening. Vegetable plants are also considered annuals, except for a few species such as asparagus. Annuals require basic care, as they need a good soil, water and fertilizer to thrive most of the growing season. Water the plants, as needed, to keep the soil moist but not soggy. Because annuals produce flowers for most of the growing season, they need a fertilizer with an equal amount of nutrients. Applying good quality 20-20-20 fertilizer that you can mix with the water in your watering can and a regular schedule of fertilizing, following the package directions, every two weeks is a good rule of thumb and will keep your plants healthy and blooming. You probably recognize some of the traditional annuals such as geraniums, alyssum, pansies, and petunias, but check your local nursery for many exciting new species and varieties available today.

Gardening Guru Tip: To extend the flowering period, make “deadheading” a habit with your annuals. Deadheading is the practice of removing the expired flowers from the plant. This encourages new flowers to develop and keeps your plants well groomed. You only need to spend a few minutes each day removing spent flowers.

Like annuals there are hundreds of perennial plants and multiple varieties to choose from. Perennials are a more “permanent” plant in your garden because they grow back every season. Many people think that perennials are expensive but remember you are investing in a plant that will last for many years as opposed to only one growing season. Also almost all perennials can be divided into additional plants after a few years of growth. Like annuals you can chose perennial plants for their growing habits, soil and sun requirements. Perennials usually have a scheduled bloom time, so most plants only bloom for a designated period, then produce seeds. Perennials are not just enjoyed for their blooms, but other characteristics, as well, for example, their structure or growth habit (climbing vines or form a carpet), leaf shape and/or colour. You may like the more traditional perennials such as bleeding heart, irises, peonies, lilies and Hostas but don’t be afraid to mix these traditional varieties with new hybrids of the same specie or of another species that you like. Perennials tend to be very low maintenance with a few exceptions. Most require the right growing conditions and once planted you make sure the garden stays adequately watered and add a slow-release granular fertilizer to the garden in the spring. In the fall, some of your perennials may need some extra care before winter comes. You may need to mulch them for the winter, prune them before the snow or even dig them up and store them in the house for the winter. A good book on perennials will guide you, or you can keep reading this column, as I will cover these topics as fall approaches.

Gardening Guru Tip: Make sure you either save the tag, that comes with your plant, or record the information it, as it is also a great source of information for planting and care of your perennial.

Whether you chose annuals, perennials or a combination of both, you can design a great garden based on what you are attracted to but make sure you match the plant to the growing conditions you have in your garden. Don’t be afraid to use your imagination and to try something new. You can combine annuals and perennials with similar habitat conditions or just plant annuals or perennials. It is your choice and I am confident you can create your very own garden design that you and all of your friends will admire. So let’s get growing!