Bonsai care (yew)
Placement
Yew is not a houseplant, so it should spend most of the year outdoors. Place it somewhere bright but shaded – it doesn’t like direct sun, especially in summer. For the best effect, a bonsai should stand on its own; choose a spot where the miniature tree is clearly visible and not “overshadowed” by other objects. Above all, the bonsai should be placed so that the viewer can clearly see its front – the tree’s most striking side.
Watering
Bonsai need regular, careful watering.
In nature, a tree’s roots grow deep into the ground. If it happens not to rain for a while, the deep roots still allow the tree to get the water and nutrients it needs. In confined conditions, a bonsai has no way of sending its roots wherever they are needed. A bonsai grows in a very small amount of soil, so it depends on watering far more than a tree growing in nature.
It is also worth noting that on hot summer days the movement of water through the plant, and its evaporation from the leaves, regulates the plant’s temperature and protects it from overheating. As long as the soil is moist, the plant can keep growing normally even in very high temperatures. A lack of water causes the plant to dry out and die.
It is also worth noting that on hot summer days the movement of water through the plant, and its evaporation from the leaves, regulates the plant’s temperature and protects it from overheating. As long as the soil is moist, the plant can keep growing normally even in very high temperatures.
How much and how often to water
How often a bonsai needs watering depends on the conditions it is kept in, the soil in the pot and the species itself. A bonsai should be watered not on a strict schedule, but when it needs it. In late spring and summer, for example, watering once a day may not be enough. There is another misconception: that watering during the hot part of the day harms the plant. In summer, it is sometimes actually essential to water a bonsai during the sunny part of the day. So don’t draw up a schedule along the lines of: “The bonsai must be watered once a day, in the evening.”
Yew needs relatively little moisture, but letting the soil dry out completely, even for a single day, very often kills the plant. Be sure to check the condition of the soil every day and water whenever it becomes necessary. Watch the moss first of all. It is easy to see when its surface is dry – it changes color,
Use ordinary tap water. Make sure the soil is wet right through after watering; otherwise only the surface may get wet while the soil deeper down stays dry.
In spring and summer the plant needs far more water than in late autumn or winter. In winter you may water the plant only once a month for the whole season (do not water a bonsai during frosts).
The time of day you water a bonsai also matters. In late spring and summer, when temperatures are high, try to water in such a way that the soil in the pot stays moist through the night. Water in the evening, after sunset. If you water only in the morning or at midday, the soil soon dries and the plant spends practically the whole night in dry soil. In autumn, when the sun is no longer so fierce, you can water your bonsai at any time of day.
Now about overwatering. When the soil around the roots is constantly wet, the amount of oxygen in it drops. This in turn damages the fine roots. The damaged roots begin to rot, and if the process is not stopped, a large part of the root system gradually rots away. As a result, the tree first weakens and, if the situation is not corrected, dies. So once you have watered your bonsai thoroughly, let the soil dry out gradually and only then water again.
Persistent rain can also leave the soil too wet. But even a week of non-stop rain will not harm the plant. The danger is when the soil stays waterlogged constantly, for an entire season.
There is one more mistake people make with watering. In summer, after a short shower, only the surface of the soil in the pot gets wet, while deeper down it stays dry. If you are not sure the soil is thoroughly wet all the way through, water the bonsai as usual. In this case the extra watering will do no harm.
Winter care for bonsai
In winter, trees are dormant, and their active growth is suspended until spring. The dormant period is just as essential to a plant’s vitality as the period of active growth. So bringing a bonsai into the warmth in winter simply because it “might get cold” is fatal for the plant. Of course, bringing it indoors for a day or two to decorate a room will do no harm. But if it spends the whole winter in the warmth, it will certainly die.
In Tbilisi conditions, a bonsai needs nothing special to overwinter. But if the temperature stays very low all day long (-10°C and below), the plant must be protected from frost. This applies above all to the roots. A bonsai’s roots are not buried deep in the ground, so they can freeze. During such spells, you can temporarily move the tree somewhere the frost won’t be as severe.
Protecting bonsai in summer
At temperatures above 30°C, unless we take special measures to protect a bonsai, the plant may be damaged or even die. How a plant copes with abnormal heat depends on its own heat tolerance and on how many hours a day the high temperatures last.
The effect of heat is easy to see on a deciduous tree. A plant cools itself through its leaves, by evaporating water. In high temperatures it quickly loses moisture. When a bonsai gets too little water in the heat, leaf temperature can reach a critical point. Wilting leaves are the first symptom of water shortage. In severe heat, a plant may go dormant prematurely (as it does in autumn). The leaves change color and fall – first those inside and at the bottom of the canopy, then the rest. When direct sun falls on a bonsai, the soil in the pot also heats up considerably. High temperatures can damage the roots as well. Under these conditions the plant becomes less resistant to diseases and pests. On conifers, however, these processes are hard to notice, because their needles don’t give such “signals”. That is exactly why conifers need special attention in summer.
A plant can cope quite well with very high temperatures if you give it normal conditions in which to function. There are a few simple ways to protect a bonsai from extreme heat. Keep it out of direct midday sun, or rig up some shade. Don’t set a bonsai on surfaces that get very hot in the sun: stone, concrete, metal. Try to raise the humidity around the bonsai: mist it more often and water the area around it. Make sure the soil in the pot never dries out completely. Watering at midday is another way to cool the roots.
Fertilizer
For normal growth and development, besides the carbon (C), hydrogen (H) and oxygen (O) that a plant takes from air and water, the plant must obtain macro- and micronutrients from the soil. The macronutrients are nitrogen (N), phosphorus (P), potassium (K), calcium (Ca) and magnesium (Mg). Various micronutrients are also needed in very small doses: iron (Fe), copper (Cu), zinc (Zn), molybdenum (Mo), boron (B), manganese (Mn), sodium (Na) and others. All of these elements are vital to the plant’s existence, the macronutrients above all. An excess or deficiency of any of them has a marked effect on the plant’s development. For example: nitrogen is needed to regulate growth, for the leaves and for fruiting. A nitrogen deficiency soon shows itself as slower growth; an excess prolongs the growth of new shoots. Nitrogen-rich fertilizer is not applied in the second half of the growing season. Phosphorus promotes the plant’s development and root growth, and strengthens its tolerance of drought and frost. Potassium gives the plant resilience to stress (very high or low temperatures, too much or too little moisture). The right amount of potassium improves the buds’ ability to overwinter and the plant’s resistance to fungal and bacterial diseases. Calcium is essential for a normal metabolism in the plant. Because there is so little soil in a pot, its nutrients are soon exhausted. That is why regularly applying a fertilizer that contains all of these elements is just as essential as watering. Without extra feeding, the plant grows weakly, its leaves and needles lose color, and it falls prey to disease more easily.
You can use either organic or mineral fertilizer on a bonsai, but you must not mix the two and apply them together. There are fertilizers made specifically for bonsai that contain all the necessary elements. They come either as a liquid or in solid, granular form. Liquid fertilizer is dissolved in water at a set dose, and the plant is watered with the solution as usual. Plants take up liquid fertilizer fairly quickly, so on conifers it is applied once every 3 weeks. Granular fertilizer acts over a longer period. It is either mixed into the soil or put into small special baskets set on top of the soil. Each time you water, a certain amount dissolves and gradually feeds the bonsai. You can order special bonsai fertilizer online.
If you can’t find such a fertilizer, you can use a general-purpose compound fertilizer sold in garden centers or flower shops. As a rule, it contains all the elements plants need. For bonsai, it is best to use one that dissolves well in water, as it is more convenient to use. The packet always lists the composition in percentages (NPK) and how much water it should be dissolved in. Take great care when feeding and work out the correct dose precisely, because too much can kill the plant. Ideally it should be NPK 10-10-10 and contain micronutrients.
Feeding normally starts in early spring, in March, and ends in autumn, at the end of September.
At Samto Kimia you can buy “Kristalon 20-20-20” fertilizer. Dissolve 1 teaspoon in 1.5 liters of water.
Misting
Misting is essential for both deciduous and coniferous plants. Start misting once the warm weather sets in, in spring, and continue until the leaves begin to fall. In summer it is best to mist every day; naturally, there is no need to do so in rainy weather. Mist the bonsai when you water it.
Some water-soluble fertilizers are also intended for foliar spraying. This promotes lush, healthy leaves that are less prone to disease. There are also water-soluble foliar feeds that give quite good results when sprayed. If you need to spray with dissolved fertilizer or a foliar feed, do it once a week, or as often as you apply fertilizer to the soil.
Diseases and pests
Like all plants, bonsai suffer from diseases and are attacked by pests. That is why it is better to spray preventively once a month from spring to autumn. Dissolve Ridomil Gold, Strobi Star and Actellic together in water at the correct doses and spray. Never spray a bonsai in an enclosed space.
