The Difference Between Annuals, Biennials & Perennials

THE DIFFERENCE BETWEEN ANNUALS, BIENNIALS AND PERENNIALS

ANNUALS (Recommended for beginner gardeners)

Annuals are easy to grow from seed and you don’t have to wait long to see the fruits of your labor. 

It’s a plant that completes its life cycle in one year or less. Annual plants grow from seeds, flower and produce new seeds in the same year.

The life cycle of an annual plant begins with germination, where the seed starts to grow and sprout. The next stage is called the vegetative stage, where the plant grows and produces new leaves and stems. The third stage of an annual plants’ life cycle is flowering. During this stage, flowers bloom and produce seed pods that will be used for next year’s growth. The last stage of an annual plants’ life cycle is called senescence which means aging or deterioration due to age. This usually occurs during winter when there are no leaves to provide protection from wind, rain or cold weather conditions. 

PERENNIALS

A perennial is a plant that lives for more than two years and persists for many growing seasons. 

Perennial seeds are those that can remain dormant in the soil for a long time and then germinate when the conditions are right. The germination of perennial seeds depends on many factors, such as temperature, moisture, light and nutrients.

The time taken for perennial seeds to germinate varies from species to species. Some take a few weeks or months while others need up to 2 years. Not all seeds germinate at the same time and most species DO NOT have a 100% germination rate. Some species need to be chilled, scarified or soaked in water in order to germinate. 

Some perennials flower the first year while others flower the following year and every year after that. Patience is the key to growing perennials from seed, however it is a great choice for gardeners who don't want the hassle of having to replant every year. Perennials are also more resistant to pests and diseases because they have an established root system that helps them survive through the winter months. 

In cultivation, some perennials that bloom most vigorously in their first year are treated as annuals or biennials and are uprooted after flowering. Tender perennials may also be grown for a season, then discarded in autumn where not hardy. Herbaceous, or soft-stemmed perennials die back to ground level each autumn, then become dormant before producing new shoots in spring. 

The top growth of many perennials dies down in autumn; the roots, safely insulated below ground, store food in order to permit rapid growth when favorable conditions return. Woody (largely trees and shrubs), deciduous plants protect themselves by shedding their leaves, the parts most vulnerable to winter cold, in autumn; their buds remain dormant until triggered into growth by increasing warmth and light in spring. Many hardy evergreens produce small leaves with a reduced surface area, which is often leathery or covered with an insulating layer of hairs to minimize the drying effects of strong winds. 

These plants often root deeply to levels where the soil will not freeze. They may also adopt a ground hugging habit or produce aromatic oils that help to conserve water and act in a similar way to antifreeze. 

BIENNIALS
Biennial plants are plants that grow for two years before they flower. They have a cycle of growth and rest. 

Like perennials, many species need to be chilled in order for germination to occur. In some regions where there are severe temperature extremes, biennials are treated as annuals. 

A biennial plant is a plant that takes two years to mature, flowering in the second year. The life cycle of a biennial plant typically starts with germination in spring or early summer, then the plant grows up to its full height over the course of one year. In the next year, it flowers and produces seeds before dying off at the end of winter or early spring.

Biennials need longer term care than annuals. Seedlings must be grown on for a season and are often raised in nursery beds before planting out.

Biennials do not always follow a strict two year life cycle and the majority of plants in the wild can take 3 or more years to fully mature.