Last updated on October 23rd, 2023 at 08:47 pm
Those who still have potted plants such as oleanders, palms and citrus species in the garden now, bring them as soon as possible into the winter quarters, so that no frost damage occurs. Only some plants are hardy enough and will survive outdoors. How to properly overwinter potted plants.
Throughout the summer, potted plants decorate our terraces and spread a breath of the south. But the wintering of exotic plants and sun worshippers makes some demands on the care. After all, almost everything that feels at home with us in the warm season comes from other climatic regions. Large temperature fluctuations, as they determine the annual cycle in Central Europe, these plants tolerate only with difficulty, especially severe frost and cold (below -5 degrees) can damage them to death.
- 1 Which plants need to go into winter quarters?
- 2 Which winter quarters are suitable for potted plants?
- 3 Proper care of potted plants during winter.
- 4 Pest infestation in winter quarters
- 5 Which plants are hardy?
- 6 Tips for wintering on the balcony and terrace
- 7 The right winter protection
- 8 Frozen plant, what to do?
- 9 FREQUENTLY ASKED QUESTIONS
- 10 How often do you need to water potted plants in winter?
- 11 Do I need to fertilize my potted plants in winter?
- 12 How do you winter potted plants outside?
- 13 Author
Which plants need to go into winter quarters?
Plants sensitive to frost
Exotic plants such as oleander, dipladenia, palms, fuchsias, citrus trees or olive and fig trees are not used to the cold temperatures in winter and must therefore be overwintered at temperatures as low as 5 degrees Celsius. It is best to place them in a bright, frost-free greenhouse for winter dormancy.
Here you can find the potted plants that are easiest to bring through the winter:
- Leadwort (Plumbago auriculata)
- Angel’s trumpet (Datura)
- Golden orange (Aucuba japonica)
- Laurel (Laurus nobilis)
- Pomegranate tree (Punica granatum)
- Oleander (Nerium oleander)
- Mediterranean snowball (Viburnum tinus)
- New Zealand flax (Phorbium tenax)
- Jewel lily (Agapanthus praecox)
- Cistus (Cistus)
Which winter quarters are suitable for potted plants?
Wintering places such as cellars or garages are often too dark or too warm. A lack of light can be remedied with special lamps, for example. Evaporators or water bowls help against dry air. If the wintering place is not ideal, the next pest infestation will not be long in coming. Oleander, for example, does not tolerate drafts and is soon attacked by spider mites in locations in stairwells. The best location for winter dormancy is therefore usually a cool, bright greenhouse or conservatory. The pots are then placed close together, and if the threat of record cold, an additional protection of textile tarpaulins or crumpled newspapers is suitable.
Proper care of potted plants during winter.
Just before wintering, it is no longer necessary to fertilize or water, otherwise the plants will begin to sprout and get long, weak shoots. During the winter, it is sufficient to always water only when the potting soil has dried completely on the surface. However, it is recommended that some species be pruned back vigorously. In this way, you eliminate possible pathogens and pests. Of course, you may eliminate flowering plants when pruning, it depends on the species. Some species also shed all their leaves in winter storage, such as pomegranate. This means that these plants then also need less light. Evergreen plants, on the other hand, always need sufficient light.
Pest infestation in winter quarters
Anti-pest sticks, already inserted into the soil in the fall, can at least thwart the first infestation. Nevertheless, the plants in the greenhouse or conservatory must be monitored. In addition to spider mites, scale insects and whiteflies are also common winter pests. A short treatment with a plant-based oil preparation will kill many insects still attached to the plant. Repot in the spring.
Which plants are hardy?
Potted plants that provide greenery on the patio or balcony all year round, are hardy and winter-hardy and can be overwintered outside in their containers, make every gardener’s heart happy. These include hardy succulents such as houseleeks, frost-hardy, cut-tolerant evergreens such as boxwood, holly or ivy, and not forgetting dwarf conifers such as mini-pine or sugar loaf spruce. Color is provided by bunch heather, heather and mock berry, which are also hardy balcony plants. Even though these plants can overwinter outside, you should provide winter protection.
Tips for wintering on the balcony and terrace
Be sure to choose frost-resistant planters, otherwise they will crack in severe cold. Good to know: Terracotta is only frost-hardy after certain firing methods. To prevent the root ball from freezing through, do not expose planters to cold air from all sides. So hang balcony boxes from the balcony parapet and place them on the ground. Back the tubs together, preferably in a sheltered place on the wall of the house. For example, an insulating layer of wood, thick cardboard or Styrofoam under the container is good.
Plants often have different requirements for their winter protection. This raises questions among garden owners year after year. Some nurseries therefore offer an overwintering service. They then take the plants over the winter and deliver them again on time in the spring.
The right winter protection
Nature takes care: Plant parts that are most exposed to the cold are usually the most frost-hardy. For example, the roots of a plant are much more likely to freeze than the shoots.
Therefore, it is necessary to protect mainly the roots, while the above-ground parts of the plant can withstand light frost and cold without protection. Every plant gets used to cold to a certain extent. It reduces its metabolism and thus growth.
In harsh locations or in areas with prolonged periods of frost, the safest method is to bury the pots in the garden: if this is not possible, such as climbing plants, the pot is thermally insulated. To do this, pack insulating material such as Styrofoam, newspapers or straw around the pot and then wrap the pot (not the plant!) with bubble wrap. From above, a thick layer of leaves or bark mulch covers the soil.
It looks more decorative if you use wire mesh to secure the foliage or straw insulation instead of foil, but this provides less insulation. If additional protection of the plant is necessary, never use air-impermeable material – this increases the risk of fungal attack. Protect the grafting site of a rose tree by using fir branches.
Most winter damage is caused by rapid freezing and thawing in the sun: tensions develop in the tissue, the cell walls tear and the plant parts die. This damage is particularly evident in wintergreen deciduous shrubs.
To avoid this, container plants are placed in the shade in winter, for example on the north side of a house wall. Alternatively, use shade netting or straw mats.
Frozen plant, what to do?
If you were late in arranging winter quarters for your plant, your plant probably won’t be completely frostbitten by the first real cold snap. Even if parts have frostbitten, there is still a chance of resprouting.
Only with third-degree frost damage, when the old wood is frostbitten, does the condition become critical for some plants. However, even a healthy oleander that is completely frostbitten above ground at minus 14 degrees usually resprouts from the rootstock.
But here the new shoots can wait until the summer, so long it takes to regenerate. Stick shoots are also relatively sensitive to frost.
FREQUENTLY ASKED QUESTIONS
How often do you need to water potted plants in winter?
Your potted plants need very little water in the winter. Therefore, water sparingly.
Do I need to fertilize my potted plants in winter?
You should not fertilize your plants during winter dormancy.
How do you winter potted plants outside?
Move your plants to a sheltered house wall and protect the pots with raffia mats, fleece, foliage or pine greenery. Wood or Styrofoam under the pot will prevent the root ball from freezing.