Rosemary is an herb native to the sunny, hot, and dry Mediterranean region. Its needle-like leaves are used to season chicken, pork, lamb, soups, tomato dishes, rice, salads, eggs, apples, wines, sauces, stews and dressings. But is your rosemary shrub getting woody? Why is rosemary turning woody at all? In this post, you will learn why rosemary is turning woody and how to keep it from turning woody.
The main reasons for rosemary turning woody are lack of pruning, plant age, overwatering and overgrowth, and rosemary plant needs regular pruning. However, it is natural for rosemary to turn woody as it is a shrub.
Rosemary tolerates hot, sunny, dry sites in summer, but prefers cooler temperatures (40-65 degrees F/4-18 C) in winter as long as the light is strong. It is very hardy and can survive a severe lack of water and sunlight, even for an extended period of time. This makes growing rosemary plants quite easy, even for beginners. Rosemary grows best in warm areas with good humidity, and shrubs can reach up several feet tall. In fact, under ideal conditions, rosemary grows so much that it can become a bit of a burden if you don’t look after it properly!
Tuscan Blue is one of the tallest varieties of rosemary. It can grow up to nearly 5-6 feet high. The leaves are broader than average and very aromatic; dark blue flowers. Golden Rain is one of the shortest rosemary varieties, about 2 to 3 feet tall and just as wide. It has golden yellow leaves and dark blue flowers. ‘Prostrate’ rosemary is great for growing in pots indoors, because it stays rather small.
Rosemary can be planted outside in the garden or inside in pots. One of the most common problems gardeners observe is that rosemary becomes woody after a while. Then only the young sprigs and leaves can be used for cooking, as older leaves have a somewhat woody flavor.
Potted rosemary plants are easy to control, but in the garden, they grow freely. Because of this, rosemary shrubs easily become woody and shabby looking. This article discusses both reasons and measures to avoid too many woody branches in rosemary.
Reasons for a woody rosemary
Lack of pruning
In the Mediterranean heat, rosemary shrubs are pruned/kept in shape naturally. Thin soils, brooding summers, and strong winds keep them neat. In our wetter, milder climate, they grow differently, so it’s important to prune them regularly – once or maybe even twice a year – to keep them in nice shape. Early spring and late summer are optimal for pruning.
So, if you have not done your regular annual pruning of the rosemary, then it is more likely that your rosemary plant will become woody. Because rosemary is a shrub, it needs to around twice bigger in width than in height.
If you would like to find a full guide on pruning rosemary in pots or shrubs, please see this post.
Dying rosemary or freeze damage
If you notice bare stems on your rosemary plants after winter, it might mean that your rosemary did not survive. Always make sure to prune your rosemary by the end of the flowering season (end of summer) and protect the plant from freezing temperatures. Temperatures below 17 degrees Fahrenheit (-8 Celsius) are too low for a rosemary, and it might not survive. If in your climate, temperatures in winter get below 20F/-7C, you can cover your shrub with a horticultural frost cover like this, which will protect by around an extra 5F.
Rosemary’s main requirements for survival are warm temperatures, lots of sunlight and the soil with good drainage. These conditions are met in the Mediterranean, where rosemary is native. If your rosemary doesn’t at least get each of these requirements fulfilled, it will not survive for too long. Rosemary needs around 10-12 hours of direct sunlight during the growing season! 6-8 hours of direct sun is a bare minimum.
Make sure that you use well-draining soil that is light, sandy and gritty. Avoid heavy soils that will take too long to drain. This will cause diseases and root rot in your rosemary. Overwatering is another cause of problems in rosemary – this plant is naturally drought-tolerant, so only water when the soil is mostly dry.
If you think your rosemary is dying, see this post for signs and tips.
Natural woodiness
Apart from any care errors that can make your rosemary woody, it is natural for a rosemary shrub to turn woody over time. That is because rosemary is a shrub, and only its leaves are harvested. The stems and branches of a rosemary shrub are not harvested. However, you can use branches and throw them on a BBQ for a nice woody smell. Because it is a shrub, it’s natural for it to turn woody.
Growing rosemary in the open ground in a garden will cause fewer problems with its care. That’s because drainage will be more optimal, and more space will allow proper drying out of the soil. Bottom stems that turn woody will have more space to spread out, because rot is often caused when water is trapped underneath the plant. Sunlight also needs to reach all parts of the plant to aid with photosynthesis and evaporation of any trapped water.
How to keep your rosemary from turning woody?
Normally, most stem growth of rosemary plants occurs in the spring and early summer in colder climates. It is more likely that when the dormant season begins, the new growth will harden off and become woody. Once this happens, the stem will never grow in length again, but it will continue to grow in diameter for the rest of the plant’s life.
However, it is perfectly normal for any rosemary plant to become woody over time. It’s in their nature. However, by pruning the rosemary regularly, we can do a pretty good job at preventing it from becoming woody. Pruning also encourages the young leaves and branches to grow quickly.
Not only pruning, but also watering the plant regularly will reduce woody growth in favor of softer, younger growth. So, make sure you water your rosemary plants properly and feed them well. But be careful with overwatering. Rosemary is a very drought-resistant plant and only needs watering when soil is dry. Achieve good drainage by using the stony and sandy soil for your rosemary and avoid heavy soil. Overwatering can easily cause root rot and other infections & diseases.
Regular pruning to prevent rosemary from getting woody
Rosemary harvesting can be easily done all year round. This will help you enjoy it all year round and spice up your cooking. Rosemary can tolerate a heavy harvest if done properly, so even a single plant can be a productive addition to the herb garden.
Always choose full length branches that are at least 8 inches long to harvest. The plant will grow well as long as you don’t cut off 1/4-1/3 of the plant. When harvesting, take 6-inch (15.2 cm) sections of new tender leaves.
However, you should be mindful of certain things when considering pruning. If you prune the plant at the wrong time and too much, then the survival of the plant will be difficult. If you leave your rosemary herb without pruning, in a few years, you will have a bare and leggy bush with no fresh shoots. However, if you prune rosemary carefully, then it will reward you with fresh fragrant growth.
Best time for pruning rosemary
Spring or early summer is the best time to prune your rosemary. This is because rosemary grows actively in the summer and responds well to pruning by encouraging new growth.
In spring or early summer, warm weather and abundant sunshine helps produce healthy new growth of leaves and branches. In winter, the plant continues to stay dormant and does not respond well to pruning.
It is better to stop pruning and also harvesting in mid-autumn to avoid stimulating new growth that may be too tender and susceptible to cold. Make it a habit to prune your rosemary around the same time each year. Regular attention will definitely make it flourish.
A good rule of thumb for pruning is to prune your rosemary 4-6 weeks before the first frost. This gives the new growth a chance to harden off before the temperatures drop outside. Never prune in winter.
How to prune rosemary to prevent woody parts?
So, since you know the importance of pruning, let’s take a look at exactly how to prune rosemary plants to prevent them from becoming woody.
To prune your rosemary, you will need a sharp pair of pruning shears. This is because the jagged cuts of dull blades could leave your rosemary vulnerable to pests or infectious diseases.
The first thing you should do is remove dead branches and faded flowers. Cut the branches right at the base and gently pluck off the flowers with your hands. Then, cut the dead shoots back to the first pair of green leaves you see, so they can form new leaves.
Then cut the outermost stems back to about 2 to 3 inches, which will stimulate new growth. Avoid cutting woody stems as this will damage the rosemary and will not stimulate new growth. Bare branches will not bud again. If you cut off too many woody parts of the plant, the plant will either die soon, or stop developing new branches in that area.
Avoid cutting below the lower leaves. If you cut off too many leaves, you could damage the plant. On the contrary, if you cut the plant too short, the rosemary will grow new woody shoots with fewer leaves or stems. So stick to the top 2-3 inches to cut shoots. Simply put, we can say that if you shorten your rosemary by a third of its size, it will remain perfectly fine.
A hard annual pruning won’t stop the woody part of the plant from expanding upwards, but it will slow it down a lot. In general, your rosemary should be 1.5-2 times wider than taller, so make sure to keep height in control.
Avoid overwatering your rosemary
Rosemary prefers full sun and light, well-drained soil with a pH between 6 and 7. First-year rosemary plants need more water to become established. However, established rosemary plants do not need frequent watering. That’s because rosemary is a drought-resistant plant. Too much watering can cause the plant to become woody. In addition, overwatered plants are more susceptible to root rot.
The most common sign of overwatering is when the tips of the silvery-green, needle-like leaves turn brown. Stop watering your rosemary immediately. A good rule of thumb is to water deeply and less frequently. This will help promote the greatest root growth.
An established plant will need to be watered every 1 to 3 weeks, depending on your climate. During dry spells, keep rosemary plants well-watered. For indoor potted rosemary, make sure that pots have drainage holes.
Generally, plants need 1 inch of rain per week during the growing season. For rosemary in the garden, it is best to water the plants with a drip or trickle irrigation systems. They release water to the soil at very low pressure. Keep the soil moist, but not over-saturated.
Make sure the soil is evenly moist and allow it to dry out between waterings. You should also fertilize your rosemary annually to encourage new growth. For a fertilizer, you can use a fertilizer for leafy crops or special herb fertilizer like this. A good rule of thumb is to water deeply and less frequently. This will encourage the greatest root growth, which is what your herbs need to thrive.
Conclusion
Older parts of rosemary naturally turn woody over time. However, only fresh growth from the top parts of the rosemary is good to eat. Top leaves have lots of flavor and smell, while bottom ones don’t. In general, proper pruning at the right time and optimal watering are key to preventing rosemary from becoming too woody. Always wait for signs that your rosemary needs watering rather than watering on a set schedule.