Often kept year round inside the house, the Yucca or Joshua tree is an outdoor plant, many species of which tolerate our harshest French climates very well due to their great hardiness. Let’s find out how to care for a Yucca, in what conditions to grow it, when to repot it and what its water needs are.
Entertain a Yucca
Perfect for all lovers of the plants seem to be unripethe Tree of Joshua has many advantages and we can salute the low level of requirements in terms of maintenance.
He is satisfied with very few things as soon as we reserve him a place in full sunand that it benefits from a well-drained soil so that its roots do not bathe in water. It thrives without difficulty inshelter from the wind, in a poor, stony or even sandy soil provided that the water does not stagnate there. The Yucca is indeed a xerophytic plant. On the other hand, a very clayey soil in which the water flows badly does not suit it at all and can even be fatal to it.
The potted Yucca appreciates a moderate misting in winter if it is located in a heated room whose ambient air is particularly dry.
During the growth period, it is necessary to add a dose ofliquid fertilizer in the irrigation water once every four weeks, from spring to late summer.
The Yucca does not tolerate drastic pruning. At most we can limit ourselves toleaf pruning whose extremity is dry and to the removal of those which are withered, stained, damaged or aging. They are cut at the base to clear the trunk. You also have to cut the wilted stems after flowering. This applies to specimens in pots as well as in the ground.
As is the case for all the plants that are kept in the house, the Joshua tree needs its leaves to be dusted from time to time with a simple sponge soaked in non-calcareous water. Specimens left outside are usually dusted by the rains.
Pests and diseases
This tough plant is impervious to disease. Only those that are over-watered or planted in non-draining soil are at risk of a fungal disease caused by the Phoma fungus. We can then see circular brown spots on the lower leaves. A spray of Bordeaux mixture helps prevent this disease, and in case of damage, do not hesitate to remove all the affected leaves and then burn them.
Some parasites like scale insects and the red spiders can infest these plants in dry weather or indoors when it is very hot, but a few mistings of preferably non-calcareous water are enough to prevent their appearance or dislodge them.
Yucca or Joshua tree growing conditions
It is recommended to mulch the plant fairly generously when it is young, in the fall, so that it can overwinter without difficulty. A good layer of gravel or dead leaves is enough to protect the young roots from severe frosts.
Some species are able to withstand temperatures of -15°C (Yucca elata), -18°C (Yucca brevifolia), -20°C (Yucca filamentosa), -30°C (Yucca baccata), or even -35°C (Yucca glauca), provided these plants are dry. At the time of purchase, do not hesitate to ask an adviser available to customers in the garden centre.
The less hardy species should be kept indoors, but in these conditions they will not flower. An indoor Yucca must be placed in the light but protected from direct sunlight especially during the hottest hours.
Repot a Yucca
It is necessary to repot a Joshua Tree every 3 or 4 years, in the spring, in order to install it in a slightly more spacious tank than the previous one, but not too much all the same. The larger specimens being difficult to handle, they can remain in their pot provided care is taken to replace 30% of the old substrate with a mixture of 50% potting soil and 50% garden soil.
Yucca Water Requirements
If the Yucca is frequently decked out with the nickname ” camel plant » it is not for nothing. Its roots store enough water to satisfy the vital needs of this plant. As a result, a Joshua Tree grown in the ground can be left outdoors in extreme drought and full sun, conditions it endures without batting an eyelid.
The young yuccas planted in the garden should be watered moderately if it does not rain, once every 7 or 8 days, especially in summer and during their first two years. As for those grown in pots, they need to be watered twice a week if it does not rain for a long time and if it is very hot. Otherwise, a small shower from time to time is enough for them.
As for the less hardy yuccas grown in pots and put back in winter, they are satisfied with a light irrigation every 10 to 12 days throughout the off-season, so that the substrate can dry out between two waterings. On the other hand, it is necessary to stop the contributions of fertilizer.
It is not surprising to be able to admire in our coldest regions splendid massifs with an exotic appearance, that is to say where the number of sunny days is not very high and where the temperatures are very below 0°C. Plant yuccas outside is therefore an excellent solution to admire their stunning flower stalks of more than 60 cm in height with which they adorn themselves in adulthood. Just choose the hardiest species. Be careful, however, not to install a Joshua Tree on passage areas because its tough leaves have sharp edges and very hard and therefore very pungent points.