If you have ever visited our garden centre you may have noticed that we have different types of plants in different locations. Like most garden centres we try to make shopping easy for you by having zones for annuals, perennials, trees & shrubs and tropicals.
Questions that we get asked fairly often are “does this come back?”; “can I grow this in a pot?” and “my xyz didn’t come back, how come?”. This is a great time to talk about the difference between annuals and perennials and our “hardiness zone”.
What is an Annual?
Annuals are plants that tend to last for ONE growing season. They germinate, grow, bloom and die from spring to fall. Annuals are grown for their showy blooms or interesting foliage; adding a pop of colour to garden beds and containers. For example the plants that we grow in hanging baskets are annuals. They are meant to be enjoyed for one season and replaced the next season.
What is a Perennial?
Perennials are plants that grow for many seasons; The tops die in the fall but they come back from the roots each spring. Perennials are perfect for garden beds as they need to be planted in the ground (to protect their roots) in order for them to survive in our climate. The do usually have shorter blooming season however they make up for it with consistent growth. Perennials provide habitat and food for birds & pollinators such as bees and butterflies. Some perennials, such as grasses, can also offer deep root systems that help guard against erosion.
So which do I choose?
The main difference between annuals and perennials is that annual plants live for only one growing season and perennial plants regrow every year. Annuals are prolific bloomers, as they are trying to produce seeds, so if you deadhead to prevent seed setting you will get abundant flowers all season long. Many gardeners will use a combination of both annual and perennial plants in their garden beds to ensure beautiful blooms for a longer period of time. If you are making container gardens it is more cost effective to use annuals because perennials will not survive the winter in a pot.
- provide quick splash of colour,maturing faster than perennials and often bloom from planting time until frost.
- a great way to take gardening one year at a time; experiment with new plants and colour schemes without making a long-term commitment.
- perfect for temporarily filling in bare spots in established gardens
- the answer for beautiful containers through the season
- do tend to cost more initially but they are a good long-term investment because they return year after year
- require less water once established, which can be especially advantageous for those who garden in drought-prone areas and want to reduce their water consumption.
- perennials that are endemic to your region offers the additional benefit of creating a welcome habitat for pollinators and local wildlife
Occasionally customers ask about containers they have seen that use shrubs and perennial grasses as a centre focus, hoping that they can overwinter a lemon tree outside (for example). These type of large, usually expensive containers, use perennials or shrubs as an annual with no intention of over wintering.
This brings us to the concept of “hardiness zones” . Some plants that we grow as annuals here on the Canadian prairie are grown as perennials in hotter climates. Hardiness zones are based on what temperatures unprotected plants can withstand. The area around Regina SK is a 3b however if you have a very protected yard and provide ample mulch or grown cover you may be able to over winter plants in the 4a category. For a map of zones see here.
When you are buying plants you may notice that some tags have the hardiness zone listed. This will give you an idea of whether or not the plant will come back in the spring, or is “hardy” for our zone. You may find tags that say “perennial” but have a hardiness zone of 5 or higher. These are not perennials in our climate. This is an issue in Big Box garden centres as independent garden centres usually order only plants that work for the climate they are in.
As always, we are happy to help you select the best plant for your needs!