are lavender perennials – Gardener Report

Some lavender plants are often mistaken for annuals as they only last one season in certain climates or poor conditions. Lavenders however are not annuals but perennial plants that can live up to 15 years (depending on the cultivar) with the right care and protection over winter. Lavender is a semi-woody perennial sub-shrub that produces new growth and blooms each year. Lavenders are low maintenance plants but do require some specific conditions and some species are not winter hardy and therefore frequently only last one year and are therefore mistaken as annual plants. Keep reading to learn which species can tolerate cold winters and how to extend the life of your lavender so it can flower and produce fragrance year after year. Why Lavenders are Mistaken for Annuals All lavender plants are perennials that are capable of living for several years. However, they are often considered annuals or treated as annuals by some gardeners. The reason for this is usually because the non-English lavender species are not cold-hardy and therefore do not survive Winter frosts. All the English species of lavender (popular varieties include Munstead and Hidcote) are reliably cold hardy are will survive cold winters with frosts and snow for several years. The Spanish, Italian, and French lavenders however will perish in freezing temperatures and are often killed by the very first frost of winter. Spanish, Italian, and French (and all other species of non-English lavender) will live for several years but they will only survive outdoors if they are planted in a mild winter climate such as those experienced in the Mediterranean region of southern Europe where temperatures rarely go below 50 ºF (10ºC ) at night. The misunderstanding of whether lavenders are annuals or perennials often comes as gardeners plant non-English lavenders that are not cold hardy into gardens that experience winters where there are frosts and freezing temperatures. These lavenders die and have to be discarded after one year, then replaced with new lavenders, which is a very expensive process. However, this is not necessary as with some knowledge you can ensure these lavenders survive the cold or simply plant the cold hardy English lavender varieties instead of the Italian, Spanish, and French species. Make 'Annual' Lavenders Last Longer than a Year There are three main issues when it comes to lavenders dying within the first year, hence the confusion about whether they are annuals or perennials: Poor drainage is a problem for lavenders all year round but becomes noticeably worse in winter due to typically higher rainfall and slower rate of evaporation. Snow and ice can damage the weaker, more vulnerable woody base of the lavender causing it to split. The wood doesn't usually rejuvenate. Planting non-cold hardy varieties of lavender in climates that experience frost. All three of these problems can be addressed with the proper care and preparation so that your lavender can live for several years. 1. Lavenders of all species can die in winter (like an annual plant) if the soil is not well drained. Lavenders need to live in soil that drains quickly and does not hold onto water as their roots need to be kept dry. Due to their Mediterranean heritage, lavenders prefer sandy or gravelly soils, as they have the ideal structure to allow water to drain away from the roots effectively and for the soil to be consistently dyer even in Winter when evaporation is much lower. Therefore it is necessary to amend the soil with around 30% sand or gravel to 70% compost to ensure lavender plants live through winter without their roots being persistently exposed to moist material. If the lavender roots are in cold damp soils then they will develop the fugal disease root rot and die after the first year, which can give gardeners the wrong impression that lavenders are annual plants. 2. Lavenders are also susceptible to frost and snow damage over winter, (even the cold hardy English varieties) if they are not properly cared for. Lavenders do not like much water over winter as they go into a state of dormancy, but if the soil is suitably amended with sand and drains very quickly, this will not likely be a problem. The bigger issue is usually whether the lavender has been pruned and shaped to resist hostile winter weather. Lavenders need to be pruned into a dense, robust mound shape ideally in early spring and again at the end of summer after the plant has bloomed. The mound shape makes it more difficult for snow and water to get into the lavender and harm the woody growth at the base of the plant. The woody growth is surprisingly weak and vulnerable to splitting if there is any weight on it, such as heavy snow or just from the effects of fluctuating temperatures. To limit the woody growth all you need to do is prune the lavender every year. This will slow down wood from forming, extend the life of the lavender, and stimulate growth that will support the seasonal, fragrant blooms. For more information, check out my article on how to prepare lavenders for winter. 3. If your lavenders are the non-English species of lavender then there are some steps that you need to take to ensure your plant will last the winter as a perennial plant should, rather than die after the first year as an annual plant would. If your climate frequently experiences frosts every winter then you should either exclusively plant the English species or you need to dig up your lavenders and transfer them to a pot. Potted lavenders have the obvious advantage of being portable. At the first sign of dropping temperatures, they will need to be brought indoors for protection. Bring the pots inside and place them by a sunny window sill, (the more sun the better). Places such as a garage, heated greenhouse, garden shed, or by a window in your house are ideal, but I would choose the window that receives the most sun as lavenders do not enjoy constant shade. If you are struggling to find a sunny window to place your lavender a good compromise is to bring the pot indoors overnight and then place it back outside in the sun during the day. Once winter turns to spring you can return your pot to the outdoors and look forward to the summer blooms. Lavenders do grow very well in pots as the drainage conditions are often favorable. For the full guide, check out my helpful article on growing lavender in pots. Be aware that problems can occur because of temperature fluctuations if the lavender is indoors overnight in a warm heated house and placed back outside in comparative cold during the day, so depending on your circumstance it may be better to place the lavender in a greenhouse or garage so that the temperature contrast isn't quite so extreme. Alternative solution. If you live in a climate where frosts and cold weather are unseasonal yet not unheard of, then you can throw a cloche or thick blanket over your non-English lavender to insulate it on cooler nights. Just make sure you remove it in the morning to allow for sunlight. Propagate Lavenders for Free Replacements Propagation is a very effective way to produce more lavenders, so if your lavenders do perish in the winter, you can replace them without significant cost. Propagation is actually very easy and doesn't require any technical knowledge or special equipment. The best time to take cutting is in the spring and summer. Lavender propagation is best explained visually so take a look at this YouTube video for an easy-to-follow guide on how to easily propagate lavender: https://www.youtube.com/watch?v=M03tfDEAijc lavenders are considered annuals as they can grow and flower in one year and then die often due to the effects of winter. The reason is that non-English lavenders are not winter hardy and therefore die after one year Key Takeaways All Lavender plants are perennials, not annuals. People mistake lavenders for annuals because they often die over winter due to damage from snow and ice, root rot in cold wet soils, or simply lavenders that are not cold hardy have been planted in climates that experience frequent winter frosts. To ensure lavenders last more than one year they need fast-draining soil amended with sand, regular pruning to help them resist the effects of cold weather, and protection from the worst of the cold weather if they are a non-hardy species. English lavenders will tolerate frosts in winter and flower the next year however Spanish French and Italian lavenders will likely die in the first frost hence why they may be mistaken for annual plants rather the perennials. Plant non-English lavenders in pots and take them inside over winter if your climate experiences regular frosts. Taking cuttings for propagation is an easy and inexpensive way to produce more plants if you have a non-cold hardy species of lavender. You can replace lavenders that did not survive the winter with your propagated plants.