What are Perennial Plants?
Perennial plants are plants that live for two or more years. Perennial plants grow for several years and go through repeated flowering and seed producing cycles before they die or put out one seed production cycle, and then die. Perennial plantings serve as a foundation for your garden and can serve various purposes such as:
• attracting wildlife and providing habitat for beneficial insects such as pollinators and predators
• food production (such as fruit trees and vines)
• medicinal uses
• ornamental uses
Perennial plants are usually easier to maintain than annual vegetable crops and once planted perennials provide a place of beauty and interest for years to come.
There are many considerations to take into account when selecting perennials:
• evergreen vs. deciduous (green year-round or lose their leaves)
• flowering, fruiting months and colors – it makes most sense choose plants that will fruit or flower when school is in session.
• size and structure – will the mature size of the plant your are planting fit properly in the space you are planting it?
• uses of plant (culinary herbs, ornamental uses, medicinal uses, habitat, food production, ect)
• light requirements – will the plant you are planting receive the appropriate amount of light throughout the year
• appropriate climatic zones
Climate Zones for Perennial Plants
To determine which plants are suitable for a climate zone gardeners refer to plant hardiness charts or “climate zones”. A plant’s “hardiness” is the the minimum temperature that it can survive in.
There are two zone charts that are commonly used in the western region: the USDA Zone and the Sunset Western Garden Zones.
The USDA Zones range from 1-13, with one being a colder zone with annual average minimum temperature of –50F or below and 13 being a warmer zone annual average minimum temperature of 40F or above. In California most locations fall between zone 7-10.
View the USDA Plant Hardiness Zone map.
The Sunset Garden Zones are similar to the USDA Zones but are more detailed allowing for a more specific match of a plant’s ideal environmental preferences and a location’s climate. There are 24 Sunset zones and the Sunset Western Garden Book is an indispensable resource that lists thousands of plants, their zones and growing information for the Western US.
Learn more about Sunset’s climate zones.
To find out your specific zone ask your nursery professional or contact your County’s Master Gardeners
Here are a few more points to consider when planting perennials:
- “Herbaceous” perennial plants die back to the ground in the winter and regrow in the spring, “Woody or Deciduous” perennials loose their leaves but not their structure, and “Evergreen” perennials keep their leaves during the winter. Keep these characteristics in mind when planning your garden’s design.
- Evergreen perennials can be planted any time of the year, but for most of California the best time of year is in the fall. This allows plants root systems to get established before their growing season and to take advantage of winter rains.
- Bare root perennials such as fruit trees and vines should be planted in the dormant season (winter months or late winter months if your ground is frozen).
- Most bulbs are planted in the fall for spring blooming dates.
Suggested Perennials and Perennial Themed Gardens for school gardens
Choosing California Native Plants
- Growing California Natives Overview
- School Gardens and Native Plants from the California Native Plant Society, plus why and what natives to plant.
- Las Pilitas Native Nursery has an online plant database plus tips and videos for planting and landscaping with native plants
- Yerba Buena Nursery has an extensive list of downloadable Garden Guides for growing native plants, plus offers expert advice and small grants to school gardens
- PlantRight.org can help to identify invasive plants in California, learn how they can damage the environment, and choose alternatives to plant.
Fruit Trees and Orchards
- Selecting Fruit Trees & Vines for CA School Gardens a list of select trees and considerations for planting fruit trees in school gardens.
- Simple and concise tips on selecting and growing fruit trees from Earth Easy
- Small scale orchard resources from the University of California
- Learn about less common fruit trees from California Rare Fruit Growers
- More on backyard orchards from Dave Wilson Nursery
Learn about edible crop planning and planting annual crops