Top 10 Perennial Herbs for your Veggie Garden

1. Chives (‘Garden’ and ‘Garlic’) – Chives (Allium schoenoprasum) are a perennial herb of the Allium family.  Hardy to zone 3, chives will surprise you in the garden when they start growing as the snow melts.  Chives may grow to a height of 12 to 24 inches and a width of about a foot.  Less of a traveler than other perennial herbs, chives may be planted directly in the vegetable garden with little fear of spreading.  If seed heads are left on the plant, they may have the potential to self sow. Snip them off and use as a salad topper, garnish or infuse them in vinegar for a delicious and aromatic touch.
   
   Chives prefer to grow in full sun and well drained soil. When harvesting, snip leaves 1 to 2 inches above the soil line and they will regrow. I recommend starting at one end of the plant and snipping across as you need them. In turn, they will regrow evenly.
   
   Chives are delicious added to eggs, potato salads, as a flavouring for sour cream, or anywhere you would add green onions.


Chives in the perennial border.

2. Sage – Sage (Salvia officinalis) is a perennial herb of the Mint family.  Also known as Common Sage, Garden Sage or Culinary Sage, one wiff and it may bring back memories of Thanksgiving and turkey stuffing.
   
   Hardy to zone 5, sage will typically flower in the second year and grow to a height and width of 2 feet. Sage leaves have a pebbly, soft texture and may grow as long as 5 inches. To harvest, either clip individual leaves or cut back the top 6 to 8 inches of growth to create a bushy habit.  Stems are green in the first year, but will become woody as they grow older. In order to prevent a lanky habit, trim back your plants in the early spring, to encourage new stems and fresh leaf development. Do not cut back too deeply however, or the plant’s growth will be greatly inhibited.
   
   Sage prefers to grow in full sun and well-drained soil.  Flowers will typically set in the second year and are a favourite of bees and other pollinators, including hummingbirds. Pick a few of these edible flowers and add them to salads or use as a garnish. 


Sage

3. Thyme – Thyme (Thymus vulgaris) is a hardy perennial herb of the Mint family.  Unlike some of the softer-leafed herbs, thyme stems become tough and branchy, as they grow older.  Preferring to grow in a full sun, well-drained location, thyme will thrive in a dry border. Plant it where you grow succulents and it will happily thrive in sandy conditions, growing into a low-lying clump.
   
   Thyme will easily grow from seed.  Start it at least 2 to 3 months before the final frost date.  As thyme grows older, softer branches will mature into tougher stems. Prune thyme back to prevent it from becoming woody and developing flowers. The more often you harvest, the more young stems it will produce.
   
   Available in a multitude of varieties, some of my favourites include lemon thyme, lime thyme, woolly time and lavender time. Thyme is hardy in zone 4.


Freshly harvested thyme.

4. Oregano – Oregano (Origanum vulgare) is another perennial herb of the Mint family. It thrives in a full sun location, with well draining soil.  Oregano does not have specific nutritional requirements, as it prefers to grow in a soil of average to low nutrition.
   
   Oregano will easily grow from either seed or cutting. If starting oregano from seed, sow seeds indoors in seed trays at least 12 weeks before the final frost date.  Since seeds are quite tiny, sow them on the soil surface and either leave them uncovered or sprinkle a thin layer of vermiculite overtop.  Oregano does require patience however, as it may take at least 2 weeks for seeds to germinate.
   
   As oregano grows, it will form a small clump. Be sure to harvest regularly to maintain it’s bushy habit. 


First year oregano, grown from seed.

5. English Lavender (i.e. Hidcote and Munstead) – There are many varieties of lavender.  However for our zone 5 climate, English Lavender (Lavandula angustifolia) is most hardy.
   
   English lavender is another member of the Mint family.  An evergreen type, the showy aromatic flowers are what we harvest.  According to OMAFRA’s Factsheet on Growing Lavender, ‘Folgate’ Lavender has been found to be most hardy for our zone 5 climate (Westerveld, 2018). To improve winter hardiness, be sure to plant your lavender near a border shrub or snow fence, as any covering or shielding will help to protect it from strong winds and severe cold.  A covering of snow is ideal.
   
   Lavender prefers to grow in full sun and well-draining soil. Although, lavender will not thrive in wet soil, it will grow better with regular access to water, especially in the first year.  Once plants are established, watering needs are reduced.
   
   Harvest your lavender flowers at the base of the flower stems, just as the flowers begin to open. This is typically around the end of July to early August. If you wait too long to harvest, you will end up with a mix of dry and dead flowers, among fresh ones. Prune the top 1/3 of your plants in early spring, in order to maintain a bushy habit. 


Freshly harvested lavender from a perennial bed.

6. Salad Burnet – Salad Burnet (Sanguisorba minor) is a herbaceous perennial, native to Europe and Asia.  A member of the Rose family, salad burnet is hardy to zone 5, often continuing to grow during the winter thaw. 
   
   Leaves are quite interesting, due their unique appearance.  The plant produces a multitude of long stems flanked by round, toothed leaflets running along the length, often up to 12 per side.  Very easy to grow from seed, sow seeds in trays approximately 6 to 8 weeks before the final frost date. As the plant develops, it will grow into a lovely mounded clump, up to 2 feet high and just as wide.
   
   The most interesting aspect of this herb is the flavour!  Young leaves are best, resembling cucumber. As the leaves grow older in the summer season, the cucumber flavour remains but becomes slightly bitter.
   
   Snip stems and add to salads, or strip the tiny round leaves off the stems and add as a garnish to soup, salad, cream cheese dip, vinegars, drinks and more.  In order to prevent leaves from aging and turning bitter, harvest regularly to encourage young leaf growth.
   
   Although, salad burnet is a perennial herb, it won’t spread out of control. To prevent the chance of seed drop, remove flowers when they develop mid-summer.


A salad burnet seedling.

7. Lovage – Lovage (Levisticum officinale) meets all parts of the herb’s definition above, since all parts of the plant are edible – leaves, roots, stems and seeds.  A member of the celery family (Apiaceae), lovage makes a wonderful alternative to its cousin.  Hardy to zone 4, lovage will greet you in early spring and will continue to produce fresh leaves right through to winter.
   
   Leave extra space for lovage in your vegetable garden, or designate a spot in a perennial border, as lovage may grow as tall as 4 to 6 feet in the second year and almost as wide.  Once established, it is very difficult to move due to its hardy root system.  It is recommended to choose a forever home at planting time, as lovage will not transplant well once established.
   
   Lovage will grow in full sun to partial shade. It requires good drainage and fertile soil.  Flower heads will develop towards mid-summer and will attract many pollinators.  Leave the flowers to go to seed, then harvest them for spices. Cut lovage stems and use them where you would use celery.  Dehydrate chopped stems and they will store well for at least a year. Then add 1 to 2 tablespoons of dehydrated lovage directly to soup stocks and it will add a wonderful flavour and aroma.


A one year old lovage plant.

8. Tarragon – Tarragon (Artemisia dracunculus ‘Sativa’) is a perennial herbaceous herb of the Daisy family (Asteraceae).  Hardy to zone 4, tarragon thrives in a full sun environment, with well draining soil.  Tarragon doesn’t require as much space to grow as other perennial herbs, growing to a maximum height and width of 2 to 3 feet. It won’t travel as much as other herbs, since it rarely produces flowers and isn’t a vigorous spreader.
   
   Fresh tarragon has a flavour reminiscent of anise or liquorice.  Harvest fresh leaves, as their flavour is most pungent when raw.  Leaves may be dried for storage, however the best flavour is preserved when leaves are chopped and added to an ice cube tray and topped with water.  Once frozen, bag the ice cubes and add a tarragon ice cube to soups and other dishes, as needed.
   
   Tarragon is one of the ingredients in bouquet garni (an herb mix used in French cuisine). It also pairs well in egg dishes, poultry, fish, salad dressing and in vinegar infusions.
   
   Tarragon is best propagated through stem cuttings and root divisions, as any seeds produced are sterile.


Tarragon

9. Viola – Viola (Viola tricolor), also known as Heartsease, is an herbaceous perennial herb, hardy to zone 4.  Although violas are traditionally known for their flowers, they’re not commonly thought of as herbs. Both leaves and flowers of the viola plant are edible. Flowers may be added to dishes as a garnish, topped over a salad, frozen into ice cubes for decorative effect, sugared or baked into shortbread cookies.
   
   Plants are fairly flexible in their growing conditions, capable of growing in either full sun or partial shade.  Preferring well drained soil, violas are hardy enough to continue flowering into winter, popping up first in the garden after a winter thaw. 
   
   Viola spreads easily by seed, showing up between flagstones, crevices or edges of a garden bed.  However, their roots are shallow and uninvasive, being very easy to remove.  Deadheading spent flowers will prevent volunteer seedlings. 
   
   Start viola seeds at least 3 months before the final frost date, as they are slow to start.
   
   Note!  Do not consume garden centre purchased viola plants. These may be sprayed with chemicals as a defence against pests. Only violas grown from seed are safe for consumption.


Violas

10. Peppermint – Peppermint (Mentha x peperita) is a wonderful herb, with a bad reputation. Known to take over a garden if planted directly in the soil, many gardeners fear adding it to their herb gardens. However, there are at least two ways to help slow down peppermint’s spread. 
    
    If choosing to plant your peppermint in the garden, plant in a container, then sink the container into the soil, leaving at least 3 inches of the pot’s rim above the soil.  Keep an eye on your peppermint plants and trim off any wandering stems as they stretch over the edge of the pot. Alternatively, use a heavy duty garden edge or border around your peppermint plants to prevent them from travelling and trim away any runaway stems.
    
    In my garden, I’ve selected a perennial border for my peppermint plants and let them spread within. As the stems leave the bed, we cut them back with our lawnmower, easily containing the plants.
    
    Peppermint is hardy in zone 3 and will grow in full sun to part shade, preferring moist soil conditions. Dry soil will inhibit its growth. Peppermint is best propagated from cuttings or divisions.


Mint grown from a rooted cutting and recently potted up.