Lavenders in pots – Gardener Report

French lavender grows exceptionally well in pots and is relatively low maintenance if you replicate the conditions of their natural environment. Here is a summery of how to care for potted French Lavender: Potted French LavenderCare InstructionsPotting mix:2/3 Multi-purpose potting mix amended with 1/3 sand for optimal drainage.Watering:Water frequently for first three months with a generous soak after planting. Only water once every 2 or 3 weeks in hot and dry weather. French lavender thrives in hot and dry conditions.Sun:Full Sun promotes stronger bloomsFertilizer:Do not add fertilizer. French lavender prefer low to medium fertility soil. Fertilizer encourages foliage growth at the expense of flowering.Pots and Containers:12-16 inches across, with several drainage holes in the base of the pot. Terracotta, clay or ceramic pots are preferred. Winter Care:Take French lavender indoors over Winter as it is not cold hardy and will not tolerate frost. Water once every 4 to 6 weeks in Winter if indoors.Pruning:Prune once a year either at the start of Spring or After flowering in the Fall.Flowering Time:French lavender flowers for several months starting in the Spring (May/June) for up to three months until the Fall. French lavender blooms for longer if in full sun.Popular Varieties:'Anouk', 'Regal Splendour', 'Ballerina' Keep Reading for more information and the best practices for caring for potted French lavender... Potting Mix for French Lavenders Soil French Lavenders prefer quick draining, sandy soil that is relatively low in fertility, with a slightly alkaline soil pH, as this replicates their natural growing conditions. Therefore the potting mix should encompass these soil characteristics. Multi purpose or general potting compost from the garden center is perfect for French lavenders. Although it is important to mix in roughly 1/3 (by volume) of the pot with horticultural sand (otherwise know as sharp sand or builders sand) or perlite. The sand or perlite with enough quantity provides the quick draining, porous structure that lavenders require. These materials also do not contribute much nutrients to the soil, so that the potting soils fertility is balanced and relatively low which is what French lavender prefers. Lavenders planted in rich soils or with added fertilizer will turn yellow as a sign of stress due to excessive nitrogen in the soil and the scent will not be as strong hence the importance of amending the potting mix with sand. Avoid ericaceous (acidic) compost as French lavender can tolerate soil with a pH of 6.5 (slightly acidic) but prefers neutral and alkaline soils (7-8). Add a table spoon of agricultural lime to increase the soils pH so that it is alkaline or mix in half a cup of wood ash as this ensures the alkaline pH that French lavenders require. Avoid these mistakes! Avoid planting French lavender in pots with soil that has moisture retaining granules as this will retain too much moisture around the roots for French lavenders. Watering French Lavenders are hardy plants when in harsh summer conditions. Not only are they drought resistant but also heat resistant and thrive in hot, dry environments that would seem harsh to other plants. (Hardy in USDA zones 7-11) French lavenders often do not require any additional watering once they are established in the pot and may only require watering in a few circumstances which I have detailed in the table. Lavenders are native to the arid climate of the Mediterranean in Southern Europe where they thrive in quick draining soils with little water. As gardeners we must mimic the conditions of their native environments by watering infrequently to ensure a healthy plant with a strong scent. Over watering potted French Lavender is the cause of far more problems then under watering as lavender is susceptible to the fungal disease root rot if the roots are sat in consistently moist soil. French Lavender ConditionsWatering Potted French LavenderAfter PlantingThe only time when French lavender is vulnerable to drought is after planting as the roots are not fully established. Water generously once every three days for the first week and the once a week for the first 3 months. Scale back watering to once every two weeks for the first year.During SummerOnce the plant is establish, French lavender often do not require any watering if outdoors and attain all the moisture they require from rain. In persistent dry, hot weather without rainfall, water once every two or three weeks with a generous soak.High RainfallIf there has been fairly consistent rainfall in the growing season (Spring or Summer months) then your potted French Lavender does not require watering. Additional watering will make the soil too moist for lavenders. In climates of high rainfall it is important to amend the potting mix with sand for improved drainage. During WinterLavender are in a state of dormancy over Winter and if left outside the plant will not require watering from late Fall until Spring. If you bring the lavender indoors over Winter for protection from freezing temperatures, water the plant once every 4-6 weeks.Over wateringYou can avoid over watering a lavender by amending the potting mix with course sand to improve drainage. Pots also provide more drainage then garden boarders. Do not water more frequently then every 2-3 weeks and you will not have any problems associated with over watering. Place in Full sun French lavender is one of the most drought and heat resistant lavender species that loves to be in full sun (ideally more then 6 hours of sun per day). The more sun the more potential there is for abundant flowers and the stronger the aroma. French lavender will not grow well in partial shade and you will have fewer flowers and leggy growth. Full sun will keep the conditions hot and dry, recreating the conditions of the lavenders native Southern Europe range. Plants in full sun grow well and are far less susceptible to diseases. Avoid using Fertilizer French lavender require low fertility soil conditions and additional fertilizer will be to the detriment of the plant in terms of: The strength of the aromaResistance to diseaseNumber of Blooms Lavenders is nutrient rich or soil with fertilizer will grow leggy, often with yellow foliage and the plant will display far fewer flowers. Fertile soils is contrary to the conditions where French lavender grows and thrives in their home range and they are specifically adapted to grow in sandy soils with little nutrients. French lavender are a low maintenance plant that is happiest and produces the most flowers in soil that is relatively nutrient poor so ensure that you add sand to the potting mix and your lavender will grow well. Choosing the Right Pot Choose a pot that has drainage holes in the base of the pot (lavenders hate moist soil) with a diameter of around 12-16 inches. This size pot ensures that there is enough capacity for soil so that the roots can establish properly and access the moisture and nutrients they require. If the pot is too small the roots will not establish as well and the lavender growth can become stunted. Clay, terracotta or ceramic pots are usually best as they are thicker then plastic and metal pots and they do not heat up in the sun as much which keeps the roots cool and prevents the soil from baking hard in the blazing sun. Just make sure that you do not place the lavenders pot on a drip tray as this will catch all the water and keep the soil moist which promotes the conditions for fungal diseases such as root rot which can kill the lavender. For examples of suitable pots, read my article, choosing the best pot for lavenders. French Potted Lavender Care in Winter French lavender is fairly tender and will require protection from frost over Winter. If you live in a climate that experiences freezing temperatures then you will have to bring the pot indoors over Winter otherwise the lavender will not survive. French lavender can only be left outdoors in mild climates such as those of California or Southern Europe. The advantage of potted french lavender is that it is easy to bring the plant indoors before the first frost of Winter. When nightly temperatures are at about 5°C (41°F) move the potted lavender into either a heated greenhouse, a garage or place the plant in a sunny window indoors. Even though the lavender is dormant over Winter, it will still appreciate as much sun as possible. The lavender exudes its sweet aroma from its foliage all year round (although it is strongest in Spring) so bringing it indoors will add some fragrance to your home. Water the lavender lightly just once every 4-6 weeks over Winter if the plant is indoors so that the pot does not dry out completely for months at a time. Return the Lavender outdoors in the Spring in a nice sunny space when you are confident there are no more frosts. For more information and best practices read my article about caring for French lavenders in Winter. Prune in the Spring for more Flowers Pruning a potted French lavender is no different to pruning lavenders in other conditions. There are two schools of thought about when to prune lavender. Either prune the plant: At the Start of Spring just as new growth emerges from the base of the plant, or...Prune in the Fall after flowering. Both work well but I have personally seen better results from pruning lavender in the Spring. This is because it is the new growth that supports the blooms and pruning in the Spring is more effective at stimulating the stems that will display the seasons flowers. Therefore I have seen more abundant flowering on lavender pruned in the Spring then lavender pruned in the Fall. Pruning every year is essential to extend the lavenders life span as pruning will slow down the formation of wood from the base of the plant. Cut back the top third of the soft, flexible growth and avoid cutting the plants woody base as the old wood does not rejuvenate. Always aim for a mound shape to help resist the affects of weather damage and to encourage the most blooms. Here is a YouTube video for a visual explanation: https://www.youtube.com/watch?v=9daVr8cFYgY&t French Lavender Indoors French lavender is the best lavender species for growing indoors as it is tolerates hot and dry conditions in the home and does not require a period of cooler temperatures during Winter dormancy to the same extent as other lavender species. The variety 'Anouk' in particular is good for growing indoors. 'Anouk' retains a compact size and will easily fit by a window and exude its fragrance. Note that the lavender will only grow indoors if they are placed in a sunny window sill. Ensure that you do not grow the lavender in a humid room of the house (such as the kitchen or bathroom) as lavender do not like humidity. The occasional breeze wafting through the foliage from a window will reduce the chance of fungal disease. Aside from this, caring for lavender indoors is largely the same as caring for lavenders outdoors. However there are a few other best practices to be aware of so read my article for more information about growing lavender indoors. Key Takeaways: Use a potting mix that is 2/3 potting soil and 1/3 aricturltral sand to ensure good drainage. Add some lime or wood ash as French lavender prefer alkaline conditions.French lavender only requires regular watering after planting. Once established in the pot, French lavender often does not require any additional watering outdoors as it is drought resistant and heat tolerant.Full sun is preferred for stronger blooms and fragrance.Do not add any fertilizer as lavenders prefer low to medium nutrient soil. Additional fertilizer will cause leggy growth with few flowers and yellow foliage.Choose a pot that is 12-16 inches across with drainage holes in the base and preferably terracotta, clay or ceramic.French lavender is not cold hardy and does not tolerate frost. Move your lavender indoors and place in a sunny window over Winter and return the plant outdoors in the Spring when their is no risk of more frost.French lavender requires pruning once per year in early Spring or late Fall after flowering. Cut the top third of the flexible growth and aim for a mound shape to help resist weather damage. pruning extends the life of the lavender and encourage more blooms and healthy foliage.