The iron tree is a real ornament in the garden in both autumn and spring. Although it is not one of the fastest growing plants, it is extremely easy to care for.
The iron tree or Persian ironwood tree (Parrotia persica) belongs to the witch hazel family. The plant is the only representative of the genus Parrotia there. This plant family owes its name to the German botanist Friedrich W. Parrot, who did a great job identifying and describing the plant at the beginning of the 19th century.
The deciduous shrub can grow up to ten meters high and spread just as wide. As a garden plant, the iron tree knows how to set atmospheric accents throughout the year. This begins with the early budding of the red-edged leaves and ends with a particularly intense and long-lasting autumn colour. The iron tree requires relatively little maintenance, but it does take a little patience for the plant to grow into a stately shrub or tree.
The Spread of the Iron Tree
The natural range of the iron tree is to be found in the Caucasus region and northern Iran. In our latitudes, the ornamental tree has found its way into gardens and parks. The plant is also represented in numerous botanical gardens, which is not least due to the attractive autumn colors.
Growth and Appearance of the Iron Tree
The iron tree is a late bloomer and hobby gardeners have to be patient until the tender little plant grows into a lush shrub. It can take years for the plant to grow and grow. Adult specimens can grow between eight and ten meters in height. The spreading side branches reach similar dimensions. The conspicuous, red-edged leaves appear as early as March. In summer, the lush green leaves are an eye-catcher. The intensive autumn colors set in as early as August and can last until the first frosts and are accompanied by atmospheric shades of red, orange and yellow. The fruits of the plant, on the other hand, are less conspicuous.
How to properly plant the iron tree
Iron trees are hardy plants that need littlerequire maintenance. Once the right location is found, the plant will take some time but will eventually gain height while staying mostly he althy and pest free. You should pay more attention to young plants, because they create the conditions for he althy growth of the iron tree.
❍ Location
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 shade, on the other hand, is gratefully accepted. When choosing a location, it should be considered that the plant wants to aim high and also needs a lot of space in its width. You will do justice to this with a unique position. Larger plants can usually no longer be transplanted easily. Young plants, on the other hand, can also be kept in a bucket and planted in a suitable location later.
» Tip: Iron trees can grow up to ten meters in height and width and need an appropriate location.
The ideal location:
- sunny
- warm
- no midday sun
- Unique Position
- no draughts
❍ Ground
The soil should be loose and permeable. The plant always needs sufficient moisture, but does not tolerate waterlogging. The ideal pH is 7. At higher levels, mixing peat into the soil can help. Heavy loamy soil is unsuitable for the plants.
The ideal floor:
- loose
- permeable
- moist
- pH value maximum 7
❍ Instructions
❶ select a suitable location
❷ water the root ball
❸ dig the planting hole
❹ ensure sufficient distance to other plants
❺ insert the plant
❻ Protect the roots
❼ Close the planting hole
❽ Press the soil down gently
❾ Water the plant
» Caution: As it has shallow roots, the iron tree is not suitable for underplanting.
How to properly care for the iron tree
❍ Casting
If the requirements in terms of soil and location are met, the plant is frugal and undemanding. Young plants and potted plants should be watered regularly. Avoid waterlogging. Older plants that are well established only need watering in dry summers.
❍ Fertilize
If the soil conditions are right, there is no need to continuously fertilize. It is perfectly sufficient to compost in the spring asAdd slow-release fertilizer to the soil. 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.
❍ More tips at a glance
- sunny location
- no blazing midday sun
- moist and well-drained soil
- Compost as long-term fertilizer in spring
- Water potted plants regularly
- Do not let the soil dry out even in winter
- Overwinter potted plants bright and cool
When does the iron tree bloom?
The iron tree surprises with its early flowering. 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 an inch long and are surrounded by hairy bracts. Overall, the flowering of the iron tree is rather inconspicuous. The five to seven sepals are green and brown from the tip.
Pruning Iron Trees
In order to support the development of an even crown, iron trees can be pruned back slightly in spring. This should be done immediately after flowering, around April.
» Caution: Cuts back into the old wood are to be avoided at all costs with the iron tree.
From bush to tree - pruning up iron trees
If you don't like the bushy growth form of the iron tree, you can grow a single-trunk tree with a little skill. To do this, the branches in the lower area of the plant must be removed in a targeted manner. However, it is important to proceed with caution in order not to let the growth form of the plant become unsightly. The natural appearance of the plant can only be preserved through targeted pruning.
Detect pests and diseases on the iron tree
The iron tree is an extremely robust plant, which is largely spared from diseases and pests. If abnormalities and signs of disease or pest infestation are observed, the first thing to do is to check the location. If the tree is too dark or exposed to draughts, this can have a negative effect, as can the blazing midday sun damage 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.
❍ Vine Weevil - Danger to theLeaves
The vine weevil takes a liking to the leaves of the iron tree. Egg-laying takes place at the roots. The larvae not only destroy the fine roots of the flat-rooted plant, but also attack the main roots that grow vertically into the soil.
What to do?
- Administer nematodes with the irrigation water
- Use Nematode Traps
❍ Phytophthora - Danger for the roots
This fungal infestation is a particular danger for the plant. The disease leads to rotting of the roots. This cuts off the supply of nutrients to the leaves and shoots and the plant ultimately dies.
What to do?
- Remove and dispose of plant
- No control agents known
- preventively avoid waterlogging
- Check the pH value of the soil and lower it if necessary
❍ Verticillium wilt - threat to 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 wilt. The fungus is deadly, especially for younger plants. Strong and stable plants are more likely to cope with the fungal attack. However, a chronic infestation is to be expected and shoots and branches can die again and again.
What to do?
- remove affected parts of plants
- Plant parts do not belong in the compost
- Remove plant and replace soil in case of severe infestation
How to propagate iron trees?
The iron tree can be propagated by cuttings and plants.
❍ Propagation by cuttings
Hobby gardeners are best advised to use this method. The cuttings are cut in summer. To do this, use a sharp knife and cut off the semi-lignified shoots about 15 to 20 centimeters long. After the lower section of the cutting has been cleared of leaves, the cutting point can be dipped in rooting powder. The cuttings are planted in a mixture of peat and sand. The soil is well moistened. To speed up growth, the cuttings should be covered with a glass or plastic hood and placed in a warm and bright place. A greenhouse is best for this. After about three weeks, new roots are formed.
» Tip: Rooting can be promoted with willow water. For this, one-year willow shoots are poured with boiling water and a dayleft to rest. The cuttings are immersed in the broth for a few minutes before planting.
❍ Propagation by planters
If the shrub retains its natural growth habit, there will be enough spreading branches to use a sinker. However, the procedure is quite complex and requires some gardening skill. First, a trough is dug into the ground around the plant. A branch of the bush is led into it. This should then be covered with soil and weighed down so that it cannot slip out again. The tip of the sinker is not covered with soil. It will take a few months before the sinker has developed its own roots and can be separated from the mother plant.
Wintering Iron Trees
Older plants are considered hardy and can withstand temperatures down to -20 degrees without additional protection. Young plants are less robust and need our help during the cold season. The trunk and crown can be wrapped with jute ribbons. Plastic foil, on the other hand, is unsuitable. The ground around the plants can be covered with coconut mats. In addition, you can apply a brushwood or leaf layer to the mats.
Container plants in winter
If the iron tree is kept in a bucket, it always needs a protected location, preferably on a house wall. The planter can be wrapped with garden fleece. Placing 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, if necessary, water it slightly.
» Tip: Iron trees should no longer be fertilized from mid-July. The nitrogen it contains makes the plant more vulnerable to frost damage.
The iron tree as 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 be the result. The plants easily tolerate topiary. Avoid waterlogging when watering. The wiring should only begin when the branches start to become lightly woody. In summer, the bonsai can be placed outdoors in a sheltered spot. In winter the plant should be kept bright and not below 18 degrees.