Coral tree, Erythrina variegata – care and wintering

In its youth, the coral tree is armed with spikes to defend its bark against browsing. At the age of 5 to 8 years, the spines fall off because the bark is then strong enough to withstand attacks.

location

In the latitudes here, the coral tree ideally spends the beautiful season on the balcony or terrace. Although it can endure temperatures around the freezing point for a short time, it should only be outdoors permanently when the mercury column constantly exceeds the 10 degree mark.

• Sunny to partially shaded position
• Prolonged shading reduces growth of leaves and flowers
• Proves to be tolerant of double digit temperature fluctuations

In its natural home, the Erythrina variegata often serves as a shade donor; a task that it fulfills within a few years thanks to its rapid growth rate. In addition, the ornamental tree scores with remarkable stability in wind and storms. Tropical plantations are therefore often surrounded by a ring of coral trees. Hobby gardeners will know how to creatively use this circumstance for wind-exposed seats in their garden.

soil conditions and substrate

The coral tree is not suitable for permanent planting in the garden due to its lack of winter hardiness. As a result, experienced hobby gardeners cultivate the ornamental tree exclusively in buckets. Planting in the ground is only possible in large conservatories or warm houses.

• Direct planting in deep, fresh, sandy-loamy soil
• Tub culture in well drained, nutrient-rich substrate
• Optionally, a proprietary mixture of garden soil, compost, sand and perlite
• Erythrina variegata thrives in both acidic and alkaline soil

The high tolerance to the nature of the potting soil results from the natural conditions at the home location. The coral tree comes from a climate characterized by rainy summers and dry winters. It accepts a brief flooding of a few days just as easily as a longer dry period. However, nobody should expect the coral tree to be permanently waterlogged.

pour

For an Indian coral tree to develop its opulent canopy in summer, it must not lack moisture.

• Keep the substrate constantly moist without causing waterlogging
• Water when the soil surface has dried
• Water preferably in the morning, right next to the root area

Even after a gentle summer rain, you should not do without the thumb test. Under the expansive crown with its dense foliage, rainwater does not necessarily reach the roots.

Despite the flexible attitude to soil pH, preferably water the coral tree with collected rainwater or pond water. Alternatively, let the tap water sit for a bit before pouring it on the tree. Ice-cold water straight from the tap will not please the tropical grove very much.

Fertilize

Both mineral-organic and purely organic fertilization are available for the nutrient supply.

• Start fertilizing in March with blue grain Entec or alternatively Hornoska
• At the beginning of July, another dose of slow-release fertilizer according to the manufacturer’s instructions
• Alternatively, apply a suitable liquid fertilizer for ornamental trees every 14 days

If it is not too complicated, you can regularly supply your coral tree with well-sifted garden compost from March to October. Here, part of the material is mixed under the substrate, while the remainder is used as a mulch layer. In spring, the additional supply of nitrogen activates growth, e.g. B. in the form of horn shavings or guano. From August, the nitrogen content is reduced in favor of phosphorus for magnificent flowering in winter. If you have well-rotted horse manure or stable manure available, add it to the compost now.

To cut

A coral tree requires a rethink when it comes to shape and maintenance pruning. Since the ornamental tree aligns its flowering and fruiting with the natural rhythm of the tropics, an autumn pruning would severely impair this year’s flowering or completely destroy it.

• Cut back coral tree after flowering
• Shorten shoots that are too long by a maximum of two thirds
• Make each incision 1-3 mm above a sleeping eye
• Cut off deadwood and thin branches at the base

In view of the special growth of an Erythrina variegata, you are welcome to go to work courageously when pruning. This is especially true if the tree threatens to outgrow you and would no longer fit into the winter quarters. If the dilemma only becomes apparent in autumn, you would be forced to rob the tree of its winter blooms by pruning it as necessary.

hibernate

When the temperatures drop in autumn, the coral tree moves to its winter quarters. For a short time, the wood can tolerate slightly below zero; it should of course only be exposed to this stress in exceptional cases. From a permanent outside temperature of 10 degrees Celsius, the Erythrina variegata should be allowed. His biorhythm is now adjusting to the tropical dry season. The better you are at simulating these conditions, the better the chances of a beautiful winter bloom.

• A bright spot in the heated conservatory is ideal
• Alternatively in light living rooms with temperatures above 15 degrees Celsius
• Water only enough to keep the root ball from drying out
• The coral tree does not receive fertilizer during this time

An Erythrina variegata sheds its entire foliage by December at the latest and makes room for the racemose inflorescence. As a rule, the coral-red flowers unfold from mid/late January to March.

Repot after winter

Since the Indian coral tree shows rapid growth, repotting is on the care plan every 1 to 2 years. Ideally, this measure takes place immediately after the successful hibernation, before the new shoot begins. The diameter of the new tub can be up to 10 cm larger than the previous planter. However, it should not have much more volume, because in this case the tree is busy trying to grow roots further instead of developing the distinctive pinnate leaves on a grand scale.

• Only use a bucket that has an opening in the bottom for water drainage
• Create drainage from inorganic materials such as gravel or grit
• Repot the coral tree and clean the root ball of used soil
• If necessary, cut out dried, rotten roots with a disinfected knife
• Fill in fresh substrate and pot the wood so that a pouring edge remains free

The amount of irrigation water should not be too generous so early after the rather dry hibernation. Watering is only gradually increased in the following weeks.

multiply

Once an Indian coral tree has been cultivated, further specimens can be cultivated very easily. You can choose between two proven methods, which are explained step-by-step below.

sticks

Cutting back after flowering also provides plenty of suitable sticks for vegetative propagation. An ideal piece of wood is 15 cm to 20 cm long, completely lignified and if possible not older than 1-2 years.

• Cut off the tip of the shoot with a straight cut
• Cut the bottom end of the stick at an angle for later reference
• Remove any leaves or wilted flowers
• Fill small pots with potting soil or peat sand and insert a stick in each
• It is essential to observe the polarity of the shoots

After the substrate has been slightly moistened, place the pots in a partially shaded, warm window seat. The process of root formation is accelerated if you put a plastic bag over each container. This measure creates a humid and warm microclimate, which has a tremendously beneficial effect on the growth of the roots. Planting only one stick per pot requires more space. In return, you are spared the later, quite tedious task of separating intertwined root strands. Incidentally, the roots will try even harder if there is a thin layer of compost at the bottom of the pot and it attracts with plenty of nutrients.

If the growing pots are completely rooted, repot the young coral trees in normal substrate to then care for them like adult trees.

sowing

The dark, long legumes contain between six and ten oval seeds. They are considered slightly toxic. If the appropriate safety precautions are observed, the small beans are ideal for sowing.

pretreatment

Like all seeds that thrive in the shelter of a fruit, they require pre-treatment in order to break through the natural germination inhibition. Since the seeds of a coral tree are about 20 millimeters in size, this procedure is easy to do.

• Rough up each seed with a file or sandpaper
• Then soak in lukewarm water for 12-24 hours
• After this preparatory measure, the actual sowing takes place seamlessly.
• Fill the growing pots with seed soil, perlite or coconut fibers
• Stick one seed 1-2 cm deep into the substrate
• Moisten and set up in a semi-shady place at 25 degrees Celsius

To ensure that this process does not take more than 2 to 4 weeks, it is advisable to use a heated indoor greenhouse. Alternatively, put a plastic bag over each pot and place it in a place that is as warm as possible and not in full sun. The lower the temperatures, the longer the germination takes. Constant moisture is important during this phase, without waterlogging forming in the substrate.

pests

Given the dry culture conditions during wintering, a coral tree is particularly at risk from infestation by spider mites . These tiny pests prefer warm temperatures and mild air dryness to spread explosively. They settle on the underside of the leaves and finally suck the sap out of the veins of the Indian coral tree. With each of their bites into the epidermis, the risk of a fungal or viral infection increases at the same time. The infestation can often be recognized by white webs. Since chemical insecticides are not desirable in the house and conservatory, the following gentle pesticides are available:

• Spray the plant temporarily daily with low-lime water
• Set up humidifiers or indoor fountains in the immediate vicinity
• Treat repeatedly with a potash soap solution until the spider mites disappear

If the size of the coral tree allows it, suffocate the pests without further ado. To do this, pack the wood in a plastic cover for a few days to completely prevent the exchange of air.

Conclusion
Hobby gardeners with a preference for exotic ornamental trees will take the coral tree to their hearts. Whether all year round in the conservatory or bright living room or throughout the summer on the balcony or terrace; everywhere the tropical guest sets decorative accents. His care is kept within manageable limits. Its species-appropriate hibernation leads to a wonderful bloom, while there is still no life stirring outside in nature. The following legumes with an impressive length of up to 20 cm also contribute to the high ornamental value of Erythrina variegata; not to mention the countless, deciduous feathery leaves.