Growing herbs outdoors in winter can keep hardy plants available for fresh seasoning and help established herbs survive until spring. Success depends on your local minimum temperatures, the herb’s hardiness, and whether it is planted in the ground or a container. Before you begin, check your growing zone and the forecast, and be realistic: many familiar herbs, including basil, are frost-sensitive and will not keep growing outdoors through freezing weather.
What You’ll Need
- Cold-hardy herb plants or seeds suited to your climate, such as thyme, chives, parsley, sage, or hardy rosemary varieties.
- A sunny, sheltered outdoor spot with well-drained soil, or a container with drainage holes and a quality potting mix.
- Loose mulch, such as straw or shredded leaves, to protect roots in garden beds.
- Frost cloth or horticultural fleece for temporary protection during cold snaps.
- Hand trowel, watering can, and clean scissors or snips for harvesting.
Step-by-Step
- Choose herbs for your winter conditions. Look up the typical lowest winter temperature in your area and compare it with the hardiness of each herb. Chives, thyme, and some sage varieties are often reliable in cold regions once established. Parsley can tolerate cool weather but may be short-lived, and rosemary varies widely: some varieties tolerate mild frost, while others need protection or a frost-free climate. Basil is not a winter outdoor crop where frost occurs. Local extension services or reputable plant labels can help confirm suitability.
- Start with established plants when time is short. Planting young herbs well before the ground freezes gives roots time to settle. In climates with cold winters, late summer or early autumn is usually better than planting just before frost. If winter has already arrived, avoid disturbing frozen or waterlogged soil. Protect an established plant, or wait until spring to plant. Seeds of slow-growing herbs may not germinate well in cold soil.
- Find sun and shelter. Select a place that gets as much direct winter sun as possible, ideally several hours a day. A spot beside a wall can reduce exposure to wind, but avoid locations beneath roof edges where falling ice or heavy runoff could damage plants. Leave enough space around herbs for air to circulate; crowded, damp foliage is more prone to disease.
- Check drainage before planting. Winter-wet soil can be more damaging than cold to many Mediterranean herbs, especially rosemary, thyme, and sage. Choose naturally well-drained ground, or improve a planting bed with suitable organic matter without creating a low pocket that holds water. For pots, use a container with open drainage holes and a free-draining potting mix; do not let the pot sit in a saucer of water.
- Plant at the right depth. Set each herb at the same depth it grew in its nursery pot, firm the soil gently, and water it in if the ground is not saturated or frozen. Follow the plant’s spacing label. Avoid heavy feeding in autumn: lush late growth is vulnerable to frost, and most hardy herbs need little fertilizer during winter.
- Protect roots and pots. Once the soil has cooled, apply a loose layer of mulch around garden-grown herbs, keeping it clear of stems and crowns so they do not stay soggy. In very cold areas, use a breathable frost cloth during severe freezes and remove or open it when temperatures rise. Small pots are more exposed to freezing than garden soil. Move them to a sheltered, unheated spot, such as against a protected wall, or insulate the pot; do not wrap foliage in airtight plastic.
- Water sparingly but check regularly. Water on mild days when the soil is dry a little below the surface, then let excess drain. Plants in containers may dry out faster than those in beds, but cold-weather growth uses less water. Avoid watering frozen soil, soaking leaves late in the day, or keeping roots constantly wet.
- Harvest lightly. Take a few leaves or small sprigs from healthy plants when needed, using clean scissors. Do not strip a plant or cut deeply into old woody stems during winter. Leave enough foliage for the herb to keep growing, and stop harvesting from plants that are weak, newly planted, or showing frost damage.
Common Mistakes
- Assuming every herb is cold-hardy: Basil, tender oregano types, and some rosemary varieties can be killed by frost. Check the exact variety and provide a protected alternative for tender plants.
- Overwatering: Cold, wet roots can rot. Check soil moisture rather than following a summer watering schedule, and ensure pots drain freely.
- Pruning hard in late autumn: Severe trimming can expose vulnerable growth and leave too little foliage. Save major shaping for the appropriate growing season.
- Using plastic directly over plants: Plastic can trap moisture or touch foliage and cause damage. Use breathable fleece, supported so it does not press on leaves.
- Expecting rapid winter growth: Short days and low temperatures slow growth, even in hardy herbs. Winter harvests are usually modest.
Tips
- Group containers together in a sheltered spot to reduce wind exposure, while keeping drainage holes clear.
- Label plants before growth slows or foliage dies back, especially where several herbs grow together.
- Use winter protection in response to the forecast. Remove or vent covers during mild, sunny weather to prevent overheating and excess humidity.
- Grow a mix of evergreen herbs, such as suitable thyme or sage, and deciduous perennials, such as chives. Their winter appearance and harvest availability differ.
- Keep tender herbs in pots only if you can move them to a bright, frost-free location when needed; a pot outdoors does not make a tender herb cold-hardy.
Troubleshooting
Leaves turn black or limp after a freeze: Wait until the weather warms before removing damaged growth. If the crown and roots are firm, the herb may reshoot. Remove clearly dead material once damage is easy to assess, and use fleece before the next hard frost.
Stems yellow or collapse in wet weather: Check for poor drainage and soft, rotting roots. Reduce watering, empty saucers, and move container plants somewhere sheltered. A plant with extensive crown rot may not recover; replace it in spring with a better-drained setup.
A pot freezes repeatedly: Move it out of exposed wind and insulate the sides, while leaving drainage holes open. If conditions are beyond the plant’s hardiness, place it in a cool, sheltered, frost-free area rather than a warm room, which may encourage weak growth.
There is little or no new growth: This is often normal in winter. Check that the plant is not waterlogged, then wait for warmer, brighter weather. Do not add extra fertilizer to force growth during cold, low-light conditions.
Plants look healthy but provide little to harvest: Reduce cutting and let them establish. Winter dormancy or slow growth limits how much foliage is available; use dried or stored herbs to supplement fresh sprigs.
Frequently Asked Questions
Which herbs can stay outdoors in winter?
It depends on variety and local temperatures. Chives, thyme, and some sage and rosemary varieties can overwinter outdoors in suitable conditions. Check hardiness locally, and protect container plants more carefully than herbs in the ground.
Can I grow herbs outside in winter if it freezes?
Yes, if you choose herbs hardy to your minimum temperatures and provide suitable drainage and protection. A fleece cover can reduce frost exposure, but it cannot make a tender herb safe through prolonged severe cold.
Can parsley grow outdoors through winter?
Parsley tolerates cool weather and may provide leaves through mild winters, especially with shelter. Hard freezes can damage it, so treat it as less dependable than established hardy perennials in colder areas.
Should I cut back herbs before winter?
Remove dead or diseased material, but avoid a severe late-season cut. Leave healthy foliage and postpone major pruning until the plant’s recommended pruning season.
How often should I water outdoor herbs in winter?
There is no fixed schedule. Check the soil and water only when it is drying out and conditions allow drainage. Containers need more frequent checks than garden beds, but both should not remain waterlogged.
Can I leave potted herbs outside during a hard freeze?
Only if the herb and its roots can tolerate the forecast conditions. Pots lose heat quickly, so move them to a sheltered location or insulate them; bring tender herbs into a cool, bright, frost-free place.