Rosemary (sage rosmarinusformerly Rosemary officinalis) belongs to the family of Lamiaceae. It does not exceed 2 meters in height. This evergreen shrub finds its place in all gardens, even the smallest ones. In Provence, it is nicknamed incense because its leaves have a camphor smell very marked. Its flowers grow in clusters and can be, depending on the variety, blue, purple or white. As for the fruit of rosemary, it is a brownish tetrakene. Let’s find out what are the best conditions for growing a rosemary whose aromatic branches are essential in the kitchen but also widely used in herbal medicine and perfumery.
Plant a rosemary
To enjoy the scent of rosemary that evokes the Mediterranean regions, just plant one in the garden or in a pot. Planting rosemary does not pose any particular difficulties, so it can be done by novice gardeners.
Planting rosemary in the ground
- Dig a hole about fifty centimeters deep and wide so that the roots are not cramped.
- Improve the quality of the soil if it is too compact. For example, it can be mixed with two large shovelfuls of coarse sand or even with gravel when necessary.
- Place a bed of sand at the bottom of the hole.
- Remove the rosemary stalk from its container.
- Untangle the roots if necessary, without damaging them.
- Install the sapling in the planting hole.
- Backfill and tamp the soil around the foot.
- Water copiously.
If you want to plant several rosemary in the ground, you must take care to separate them from each other by about 55 cm if it is a variety with an upright habit, and it is necessary to reserve a good square meter by creeping rosemary.
Plantation du rosemary en pot
This shrub also likes a perforated bottom tray and large enough for its roots to have enough room. The rosemary is then placed in a mixture of 30% sand and 70% potting soil. Once the plantation is finished, it is advisable to water generously then to place the rosemary in pot in an area located in full sun and sheltered from the prevailing winds.
Growing a rosemary
rosemary is planted in autumn in the most southern regions, and preferably in spring in less clement climates. It prefers to be installed in a slightly acidic soil, well drained, and can completely acclimatize if the soil is moderately calcareous. We can therefore appreciate its low requirement in terms of soil quality. It is above all necessary to ensure that the earth can never be waterlogged. As for the preferred exposure of this southern shrub, the full sun is rigorous.
Caring for a rosemary
Rosemary is without a doubt one of the easiest plants to grow.
This shrub native to the Mediterranean Basin afraid of humidity in winter which can be much more detrimental to it than dry cold if it remains moderate because rosemary does not tolerate extreme cold well. In any case, it is essential that his soil is drainedand even under extreme heat, watering is not necessary because rosemary has very low water needs that the rains are enough to meet.
Apart from watering after planting the shrub, it only needs to be watered afterwards to prevent its leaves from withering, even turning brown or falling, which can only happen in the event of extreme and prolonged drought.
You can at most moderately cut back a few years old rosemary if it has taken a little too much height or even if it starts to thin out at the base. Otherwise, it does not necessarily need regular pruning since the harvest is enough to shorten the branches.
It may be useful to add nitrogen after harvest. Generally speaking, rosemary thrives particularly well in soil rich enough to meet its potassium, magnesium, nitrogen, but also sulfur and phosphorus. However, many gardeners have had very beautiful rosemary for years, without regularly fertilizing the soil.
Protect from the cold
If the temperatures are likely to drop below -8°Cit is strongly recommended to protect a young rosemary with a winter sail. Specimens grown in pots can also be covered and then placed against a wall that benefits from good sunlight.
Pests and diseases
Rosemary is not not particularly prone to pests. At most we can see some mites on the underside of its leaves in a particularly dry and hot environment, which can cause small yellow spots on the foliage. A few sprays of rapeseed oil or the use of a pyrethrum-based product (preferably without chemical ingredients) are generally enough to eradicate the parasites.
On the other hand, it can be touched by a cryptogamic disease, the botrytis or gray rotdue to the presence of a pathogenic fungus : Botrytis cinerea. This problem strikes rosemary especially in the event of too much humidity, especially in a cold region. This fungus is said to be polyphagous because it feeds on the living tissues of rosemary, and many other plants for that matter. The warning signs are the browning partial or total branches that gradually take the shape of a crozier due to the inexorable curvature of their end.
Pour treat rosemary botrytisit is advisable to spray it generously with a horsetail decoction. Diseased branches must be removed and then burned. Note that this disease can also appear on rosemary plants that are planted too close together. Adequate space between the feet allows air to circulate better, which is why it must be taken into account when planting.
Harvest the rosemary
The picking should remain moderate in very young one-year-old plants, and becomes more and more important over the years. The ideal is to harvest as needed, when the weather is warm and not raining. Note, however, that rosemary is harvested throughout the year except on frost days whenever possible.
Harvesting therefore makes it possible to prune segments of branches, which promotes their branching. In this way, new aromatic leaves will develop. A very sharp pruning shears is enough to make a clean pruning.
The freshly harvested rosemary can be kept for three days at room temperature, in a vase filled with water, and one week in the vegetable drawer of the refrigerator, provided that care has been taken to wrap it beforehand in a damp paper towel. To freeze it, it is necessary to chop the rosemary leaves as soon as they return from the garden so that they keep their aroma, and to distribute them either in very small freezer bags or in ice cube trays. This will allow you to take only the desired amount afterwards.
Rosemary can keep for several months after having sun dried for a few hours. It is then necessary to form bouquets and then store them in paper bags that can be hung in the cellar or in any type of cool, dry and ventilated room. Finally, you should also know that rosemary flowers are edible. Their flavor is milder than that of the leaves because they contain less essential oil. They are preferably eaten raw because they have more taste that way, but they can also be infused. They flavor meats, vegetables, fruits, dairy desserts and ice creams.