The iron tree is a real ornament in the garden both in autumn and spring. Although it is not one of the rapidly growing plants, it is extremely easy to care for.© emer - Fotolia.com
The iron tree or Persian ironwood tree (Parrotia persica) belongs to the family of witch hazel plants. The plant represents the only representative of the genus Parrotia there. This family of plants owes its name to the German botanist Friedrich W. Parrot, who at the beginning of the 19th century earned services to determine and describe the plant.
The deciduous shrub can grow up to ten meters high and spread out just as wide. As a garden plant, the iron tree knows how to set atmospheric accents throughout the year. This begins with the early sprouting of the red-rimmed leaves and ends with a particularly intense and long-lasting autumn color. The iron tree requires relatively little maintenance, but it takes a little patience for the plant to grow into a stately shrub or tree.
The spread of the iron tree
The natural distribution area of the iron tree can be found in the Caucasus region and northern Iran. In our latitudes, ornamental trees have found their way into gardens and parks. The plant is also represented in numerous botanical gardens, which can be explained not least by the attractive autumn colors.
Growth and appearance of the iron tree
The iron tree is a late developer and hobby gardeners have to be patient until the tender plant becomes a lush shrub. It can take years before the plant grows and grows. Adult specimens can grow between eight and ten meters in height. The protruding side branches reach similar dimensions. The striking, red-edged leaves appear in March. In summer, the lush green leaves are an eye-catcher. The intensive autumn colors begin in August, which can last until the first frosts and are accompanied by atmospheric shades of red, orange and yellow. In contrast, the fruits of the plant are less noticeable.
How to plant the iron tree properly
Iron trees are robust plants that require little maintenance. Once the right location has been found, the plant will need some time, but will eventually gain height and remain healthy and free of pests. You should pay more attention to young plants, because they create the conditions for healthy growth of the iron tree.
Iron trees come from warm and sunny areas. However, if the tree is placed in the blazing sun, the leaves can be damaged. You should avoid particularly blazing midday sun. Light shadows, on the other hand, are gratefully accepted. When choosing the location, it should be borne in mind that the plant wants to go high and requires a lot of space in its width. You will do just that with a unique position. Larger plants are usually no longer easy to transplant. You can also keep young plants in a bucket and later put them in a suitable location.
" Tip: Iron trees can grow up to ten meters in height and width and need an appropriate location.
The ideal location:
- no midday sun
- no drafts
The floor should be loose and permeable. The plant always needs sufficient moisture, but does not tolerate waterlogging. The ideal pH is 7. At higher values, adding peat to the soil can help. Heavy clay soils are unsuitable for plants.
The ideal floor:
- pH maximum 7
❶ Select a suitable location
❷ Water the root ball
❸ Dig out the planting hole
❹ Make sure there is sufficient distance to other plants
Einsetzen Insert the plant
❻ Protect roots
❼ Close the planting hole
❽ Press the floor slightly
Ang Water the plant
" Attention: As a flat root, the iron tree is not suitable for underplanting.
How to properly care for the iron tree
If the soil and location requirements were met, the plant is frugal and undemanding. Young plants and container plants should receive regular watering. Avoid waterlogging. Older plants that have already grown well need watering only in dry summers.
If the soil conditions are right, there is no need to fertilize continuously. It is sufficient to add compost to the soil as a slow-release fertilizer in spring. Bark mulch ensures that the soil does not dry out and can also be understood as a natural fertilizer. If the iron tree is kept in a bucket, it has a higher nutrient requirement and should be supplied with mineral fertilizer at monthly intervals.
❍ Overview of other tips
- sunny location
- no blazing midday sun
- moist and permeable soil
- Compost as slow release fertilizer in spring
- Water container plants regularly
- Do not let the soil dry out even in winter
- Hibernate container plants bright and cool
When does the iron tree bloom?
The iron tree surprises with its early bloom. The flowers appear between January and March, at the same time as the leaves. An inflorescence comprises between eight and ten flowers. The flower heads can be a little over a centimeter long and are surrounded by hairy bracts. Overall, the flowering of the iron tree is rather unremarkable. The five to seven sepals are green and brown from the top.
Cut back iron trees
To support the formation of an even crown, iron trees can be easily cut back in spring. This should happen immediately after flowering, i.e. in April.
" Attention: Cutting back into the old wood is absolutely to be avoided with the iron tree.
From shrub to tree - open the iron trees
If you don't like the shrub-like habit of the iron tree, you can use a bit of skill to grow a single-stemmed tree. For this, the branches in the lower area of the plant must be removed in a targeted manner. However, it is important to proceed carefully so that the growth habit of the plant is not unsightly. The natural appearance of the plant is only preserved through a targeted pruning.
Identify pests and diseases in the iron tree
The iron tree is an extremely robust plant that is largely spared from diseases and pests. If abnormalities and signs of illness or pests are observed, the first thing to do is to check the location. If the tree is too dark or is exposed to drafts, this can have the same negative effects as the blazing midday sun damages the leaves or permanent waterlogging can cause the entire plant to die. If location and maintenance errors can be ruled out, a fungal infection or pest infestation can be assumed.
❍ Weevil - Danger to the leaves
The black weevil likes the leaves of the iron tree. The eggs are laid at the roots. The larvae not only destroy the fine roots of the flat root, but also attack the main roots that grow vertically into the soil.
What should I do?
- Administer nematodes with the irrigation water
- Use nematode traps
❍ Phytophthora - danger to the roots
This fungal attack is a particular danger for the plant. The disease causes the roots to rot. This prevents the leaves and shoots from being supplied with nutrients and the plant ultimately dies.
What should I do?
- Remove and discard the plant
- no pesticides known
- take preventive measures to avoid waterlogging
- Check the pH of the soil and lower it if necessary
❍ Verticillium wilt - danger to the entire plant
At first glance, the damage caused by this disease is comparable to a lack of water. However, wilting of the leaves can also indicate Verticillium wilting. The fungus is especially lethal to younger plants. Vigorous and stable plants are more likely to cope with fungal attack. However, chronic infestation is to be expected and shoots and branches can die off again and again.
What should I do?
- Remove infected parts of plants
- Parts of plants do not belong on the compost
- in case of severe infestation, remove the plant and replace the soil
How can iron trees be propagated?
The propagation of the iron tree can be done by cuttings and subsidence.
Durch Propagation by cuttings
Hobby gardeners are best advised with this method. The cuttings are cut in summer. Use a sharp knife for this and cut off the half-wooded shoots about 15 to 20 centimeters long. After the lower area of the cutting has been cleared of leaves, the cut can be dipped in rooting powder. The cuttings are placed in a mixture of peat and sand. The floor should be moistened well. To accelerate growth, the cuttings should be covered with a glass or plastic cap and placed warm and bright. A greenhouse is best suited for this. After about three weeks, new roots are formed.
" Tip: Rooting can be promoted by willow water. For this, boiling water is poured over annual willow shoots and left to rest for a day. The cuttings are dipped in the broth for a few minutes before planting.
❍ Increase by lowering
If the shrub retains its natural growth form, there will be sufficient spreading branches to pull a subsidence. However, the procedure is quite complex and requires a little gardening skill. First, a gutter is drawn into the ground around the plant. A branch of the shrub is led into it. This must then be covered with earth and weighed down so that it cannot slip out again. The tip of the sinker is not covered with earth. A few months will pass before the subsidence has developed its own roots and can be separated from the mother plant.
Hibernate iron trees
Older plants are hardy and can withstand temperatures down to - 20 degrees without additional protection. Young plants are less robust and need our help in the cold season. The stem and crown can be wrapped with jute ribbons. Plastic film, however, is unsuitable. The floor around the plants can be covered with coconut mats. In addition, you can apply a layer of brushwood or leaves to the mats.
Container plants in winter
If the iron tree is kept in a bucket, it always needs a protected location, ideally on a house wall. The planter can be wrapped with garden fleece. The placement of the planter on a polystyrene block also protects against frost. The root area can be covered with straw or brushwood. On frost-free days you should check the soil and water it lightly if necessary.
" Tip: Iron trees should no longer receive fertilization from mid-July. The nitrogen it contains makes the plant more vulnerable to frost damage.
The iron tree as a bonsai
As a bonsai, the iron tree grows rather slowly and needs a lot of light and high humidity. At temperatures below 20 degrees, leaf fall can result. The plants tolerate shape cuts without any problems. Avoid waterlogging when watering. Wiring should only begin when the branches start to lightly wood. In summer, the bonsai can be placed outdoors in a protected location. In winter, the plant should be kept bright and not below 18 degrees.