Growing Medicinal Herbs: Know Your Plant Lifespans | Harvest Health Foods
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Growing Medicinal Herbs: Know Your Plant Lifespans

By:
Maria Noël Groves, RH (AHG)

What are Plant Lifespans?

Some herbs need to be planted anew each year, a few live on a specific two-year cycle, and others will outlive you, all of which depends on your zone and freezing temps.

Plant Lifespans
Type Lifespan Examples
Annuals Dies after frost or setting seed. Replant or let self-seed.
  • calendula
  • dill
Perennials Returns each year.
  • lemon
  • bee balm
  • most other herbs
Biennials Produces only herbaceous growth the first year, flowers and fruit/seed the second year, then dies.
  • burdock
  • mullein
  • the deadly foxglove
Tender Perennials Survives winter only in warm climates, otherwise treated as an annual or brought indoors in cold climates.
  • lemongrass
  • lemon verbena
  • gotu kola
  • bacopa
  • ashwagandha
  • rosemary
Short-Lived Perennials Dies off easily or within about 3 years.
  • artichoke (in warm climates)
  • Korean mint
  • St. John's wort
  • some mallows

In It for the Long Haul: Some Medicinal Plants Take Longer to Establish

Most of the plants discussed in Grow Your Own Herbal Remedies by Maria Noel Groves can be harvested the same season you plant them, but a few take longer to get established. This might be a deciding factor for whether or not you want to grow a particular plant, especially if you want to make medicine pronto or don't anticipate being in the same place for very long.

In some cases--like wild cherry bark and birch--you can usually find established wild trees to prune instead.

Generally speaking, while you could harvest the roots of most perennial plants within the first year or two of planting, some take longer to "ripen."

It can take several years for shrubs and trees to begin producing flowers and berries. This will depend on the age of the plant you planted as well as the species and growing conditions. (Pay more for an older tree, and it may produce more quickly than a spindly bare root sapling.) Most will grow faster and produce more flowers and fruit with full sun, good soil, and regular moisture.

Medicinal Plants That Take Longer to Mature

Here are a few examples of popular medicinal herbs that take more time to mature.

Plant Maturation
Type Timespan Examples
Garlic Planted in fall, harvest the following summer.  
Biennial Roots Fall of first year or spring of second (before it flowers).
  • mullein
  • burdock
Most Perennial Roots 2 to 3+ years (but if you're weeding babies out, use 'em).
  • yellow dock
  • marshmallow
  • valerian
  • elecampane
Echinacea Roots 3 to 4 years.  
Black Cohosh Roots 3+ years.  
Mimosa Bark/Flower 2+ years.  
Roses/Hips 3 to 5 years  
Elderflowers/Berries 3 to 5 years.  
Hawthorn Flowers/Berries 3 to 10 years.  
Linden Flowers 5 to 10 years  
Most Bark 2 to 5 years (or as soon as they're big enough to prune).
  • cramp bark
  • wild cherry
  • mimosa
  • birch

Sources

Excerpted from Grow Your Own Herbal Remedies by Maria Noel Groves. Used with permission from Storey Publishing.