How to Grow Mint: A Toronto Master Gardeners Guide

Mint (Mentha spp). Mint is a perennial herb that is hardy to Zone 5 or lower. Mint is grown for its leaves, which are used to make mint teas as well as many cooked dishes. There are several different varieties, each with its own flavour. Some varieties are more popular in cooking though this may, to some extent, be a matter of taste. Spearmint (Mentha spicata) and peppermint (Mentha x piperita) are the most commonly used.

Cultivation: Mint spreads very easily and can become invasive. In the garden, grow mint in a completely contained area such as a large container or a bottomless pot or pail buried so its rim is about two centimetres above ground level.

Mint can be propagated by dividing or rooting stems in moist potting medium. It can be grown from seed, but germination is slow and seeds my not come true, so it is easier and more reliable to propagate it by stem or root cuttings. In the garden, mint should be planted in moderately fertile water-retentive soil and must be kept moist during hot weather. Mint prefers sun but will tolerate part shade. Container-grown plants, whether in-ground or above-ground, will rapidly become root-bound and should then be divided.

Mint can be harvested any time that growth is apparent. Pick leaves frequently to promote new leaf growth and a compact form. Without trimming, mint can grow to 60 centimetres tall or more.  Mint dies back to the ground in the winter.

Mint is sometimes affected by fungal diseases such as mildew or rust. Control fungal diseases by removing affected shoots and ensuring good air circulation. Dispose of infected plants.

Jamaican bush mint (Satureja viminea, sometimes Micromeria viminea or Clinopodium vimineum) is a not a true mint but is a tropical plant with minty-flavoured leaves, used in some Caribbean dishes and herb teas. It can be grown in a pot (outdoors in summer and indoors for the winter) where it needs bright light and good drainage. Do not overwater.

Disclaimer: Toronto Master Gardeners does not advise or recommend herbs for medicinal or health use. Any information in the recommended resources should be regarded as being for educational purposes only and should not be considered as a recommendation or an endorsement of any medical or health treatment.

For more information:

The Herb Cottage https://www.theherbcottage.com/savory-varieties/

The National Gardening Association https://garden.org/learn/articles/view/1237/

OMAFRA http://www.omafra.gov.on.ca/CropOp/en/herbs/culinary/mint.html

Richters Herbs https://www.richters.com/Web_store/web_store.cgi?searchterm=jamaican+mint&search_catalogue_button=Go

RHS Grow Your Own Herbs: Mint https://www.rhs.org.uk/advice/grow-your-own/herbs/mint

University of Illinois extension: Growing Herbs: Mint https://web.extension.illinois.edu/herbs/mint.cfm

Washington State University: Managing Powdery Mildew on Mint

https://plantpath.wsu.edu/dajohn/wp-content/uploads/sites/2195/2014/06/PowderyMildewMint.doc#:~:text=Powdery%20mildew%20appears%20on%20mint,Colonies%20turn%20gray%20with%20age

Date revised: December 2021

Prepared by the Toronto Master Gardeners, these Gardening Guides provide introductory information on a variety of gardening topics.  Toronto Master Gardeners are part of a large, international volunteer community committed to providing the public with horticultural information, education and inspiration.  Our goal is to help Toronto residents use safe, effective, proven and sustainable horticultural practices to create gardens, landscapes and communities that are both vibrant and healthy.

Statement on Invasive Plants: When choosing plants, avoid invasive plants, which can spread quickly and dominate gardens.  Invasive plants are sold by nurseries, big box stores or even at community plant sales.  Invasives may already be present in your garden.  They can invade gardens by spreading from under a neighbour’s fence or may be transported by wildlife.  For beautiful, sustainable options to invasive plants, see the Ontario Invasive Plant Council’s “Grow Me Instead – Beautiful Non-Invasive Plants for your Garden” at https://www.ontarioinvasiveplants.ca/resources/grow-me-instead/before purchasing or accepting “gifts” of plants.

Statement on Home Remedies: The Toronto Master Gardeners do not recommend home remedies, as these have not been proven effective through scientific investigation, and may even damage other living organisms in the soil or plants in your garden.  There are other garden friendly options you can use.

If you have further gardening questions, reach us at our gardening advice line 416 397 1345 or by posting your question here in the Ask a Master Gardener section.  To book Toronto Master Gardener volunteers for talks, demonstrations, advice clinics, or other services, please contact us at 416 397 1345  or bookamg@torontomastergardeners.ca