Prune & propagate Dipladenia, Mandevilla & Sundaville

Mandevilla species originally migrated to Europe for cultivation as houseplants. In the meantime, the busy perennial bloomer has mainly established itself for summer garden planting.

Can Dipladenia be pruned?

All species of the richly populated genus Mandevilla are characterized by a high tolerance to pruning measures. However, a pruning is not absolutely necessary. However, if you leave the distinctive flower beauty to itself, it will quickly dance on your nose. Where the climbing plant finds support, it tends unstoppably in all directions. With the help of the pruning shears, you can keep the fast-growing summer flower under control.

It is important to note that the milky sap of Dipladenia, Mandevilla and Sundaville is poisonous as they are classified as dogbane plants. Therefore, experienced hobby gardeners never do without protective work gloves when cutting their plants.

Choose the right time

One of the outstanding characteristics is that Mandevilla always blooms on this year’s shoots. This circumstance gives hobby gardeners a certain degree of flexibility with regard to the right time for a shape and maintenance cut.

• The best time for pruning is spring, just before new shoots appear
• Alternatively, Mandevilla are pruned in the fall before being put away
• Do not prune in full sunshine or after the first frost

Thanks to the good-natured pruning tolerance of this versatile plant species, corrective intervention is possible at any time. If individual tendrils turn in an undesirable direction during the summer, the Dipladenia can be trimmed without further ado. If you have planned a place for your Sundaville as a bushy houseplant, it will need to be pruned several times anyway so that a compact habit is manifested. The same applies to cleaning withered and faded parts of plants in order to maintain a well-groomed appearance.

The optimal cut

Regardless of whether a Dipladenia thrives as a woody shrub or herbaceous climbing plant, the following premises apply to professional pruning:

• Cut back shoots that are too long by half or two thirds
• Cut dried, deformed or diseased branches at the base
• Make each incision 1-2mm above an outward facing eye
• Hold the scissors at an angle so that the water runs off better

If space in the winter quarters is tight, you are free to radically cut back Dipladenia, Mandevilla and Sundaville. At least 1-2 buds must remain on the main stem of the plant so that it will sprout again next spring. Side shoots can be completely removed.

Diverse ways of propagation

The versatile Mandevilla opens up a wide variety of ways of propagation for recreational gardeners. Depending on the current level of their skills, the range extends from easy to medium.

cuttings

Every pruning leaves a lot of basic material for the offspring of more Dipladenia. Discard any shoots that are 10cm to 15cm long and have at least 3 pairs of leaves. If they appear strong and healthy, it would be a shame if they died on the compost heap.

• Defoliate each cutting, leaving the top pair of leaves standing
• Fill small growing pots with moist peat sand, coconut or wood fibers
• Insert one cutting at a time so that only the two leaves are visible
• Ideally, dab the lower cut in rooting powder beforehand

A constant temperature of 23 to 27 degrees Celsius is required for rooting. A heatable mini greenhouse is ideal for ensuring this permanent warmth. Alternatively, put a plastic bag over each pot and place it on the warm window sill. As sun-loving as an adult Mandevilla may be; at this stage of propagation, it must not be exposed to direct sunlight. The south window of the house is therefore less suitable than the west or east window.

In the following period, the cuttings are kept slightly moist with a spray mist. Regular ventilation of the greenhouse or the plastic hood must not be missed to prevent mold growth. With a new shoot, a cutting announces that the underground rooting is successful. Once it has fully rooted the seed tray, it is repotted in substrate for adult Dipladenia and cared for accordingly.

lowering

Climbing plants, such as Mandevilla, offer their followers a variant that is as simple as it is promising for the creation of large offspring. Since the shoots are designed to climb, they have a corresponding flexibility. Resourceful hobby gardeners use this fact for propagation.

• Pull one or more semi-lignified, healthy shoots to the ground in early summer
• Where they touch the ground, make a 10 cm deep furrow with a spade
• Defoliate each sinker in the middle and score lightly with a razor
• Place in the gutter, cover with soil, moisten and weigh down with stones

The tip of the shoot sticks out of the ground and is attached to a small wooden stick with string. Throughout the summer, the sinkers remain attached to the mother plant and only receive a little water every now and then. During this time, an independent root system develops from the wound tissue. If the dipladenia is freshly emerging from the tip, carefully pull on the sinker. If you feel a strong resistance, the shoot can be separated from the mother plant with a sharp cut. Then dig up the Sundaville broadly so as not to injure the still tender roots. Potted in normal soil, cultivate the young plant indoors throughout the winter to plant out in the following spring.

Incidentally, the lowering method can be seamlessly transferred to Dipladenia in tub culture. In this case, do not pull the shoots to the ground, but into an adjacent pot. This can either be filled with conventional substrate or with nutrient-poor soil. The advantage of lean soil can be seen in the fact that the sinker works harder on root formation. You can also speed up this process by inserting a layer of nutritious compost under the lean food.

sowing

If you love a challenge as a recreational gardener, then you favor propagation by seed. High-quality seed is available in specialist shops and in special online shops. In this case, you are not tied to a fixed time for the project. Spring is ideal because later on the seedlings on the windowsill will find sufficient light conditions that support rapid growth and early flowering.
The quality of the seed soil determines the success rate of germination

Conventional potting soil is unsuitable as seed soil. Opt for a nutrient-poor substrate that is permeable and airy. If you buy a product from a store, add sand, perlite or vermiculite to make up a third of it. If you have any cactus soil left over, use it to sow the Mandevilla seeds. Experienced hobby gardeners advocate coconut fibers, which on the one hand have excellent air permeability and on the other hand can store water very well. Since you cannot rule out the possibility that viruses, fungal spores or insect eggs are hidden in the seed soil, disinfection using heat is advisable. The substrate is placed in a fireproof bowl in the oven for 30 minutes at 150 to 180 degrees top and bottom heat. After cooling down, you have sparkling clean soil at your disposal. This procedure is not necessary when using Kokohum.

Instructions for sowing

• Fill a seed tray or seed pots with seed compost or coconut hum
• Mix the tiny seeds with a little bit of bird sand to spread them out evenly
• Sieve very thinly with substrate and moisten with a fine spray mist
• Place in a bright place at a temperature of 25 degrees Celsius

Sowing in a greenhouse offers the best chance of rapid germination within 2 to 4 weeks. Alternatively, use the same method as for propagation from cuttings, using a plastic bag as a hood.

pricking

If the general conditions are right, life will stir in the Dipladenia seeds after a short time. Two cotyledons develop, which are quickly followed by other true leaves. Depending on the success rate, sooner or later the seed pot will become too small. The next step in propagation by sowing is isolation, referred to by experts as pricking out.

• Fill small pots with special potting soil or peat sand
• Lift a strong seedling out of the substrate with a pricking stick
• If necessary, trim roots that are too long with scissors
• Drill a small planting hole in the fresh substrate with the pricking stick
• Insert the small Mandevilla in it and moisten it slightly

The young plant may be planted a little deeper than before. However, the cotyledons must still be above the ground.

A mini greenhouse, which creates a conducive warm and humid microclimate, is ideal for further cultivation. From now on, the plastic bag hood will be dispensed with because there is a growing risk that the leaves will touch the material, which inevitably leads to rot.

Conclusion
Dipladenia not only impress with a lavish continuous flowering, but also with a good-natured tolerance to pruning. You are therefore free to choose the appearance of your Mandevilla using the secateurs. The key time for pruning and topiary is early spring. Optionally, prune the tropical climbing plant in autumn before it moves to its winter quarters. In principle, light corrective cuts can be made without hesitation during the entire vegetation period. If you would like more specimens of this distinctive flowering grace, you can choose from a variety of propagation techniques. The spectrum ranges from uncomplicated propagation of cuttings to summer planters to more demanding sowing.