Many a gardener wonders in spring why the supposedly hardy lavender did not survive last winter and froze. In fact, you can do quite a lot wrong when overwintering this rather less robust plant - even if some guidebooks claim the opposite. The most common mistakes include choosing the wrong variety, the wrong location, a lack of winter protection or watering too often/wrongly. In very cold but sunny winters, lavender also runs the risk of drying out.

Winter hardy, hardy or frost hardy?

First of all, when buying young lavender plants, you should pay close attention to the names given in terms of winter hardiness or frost hardiness. Many an uninformed employee of a garden center also confuses the terms "hardy" and "hardy" and thinks they mean the same thing. However, this is wrong, because hardy varieties are hardly suitable for overwintering in the garden. Plants that can only withstand temperatures below freezing for a very short period of time are also described as winter-hardy - but they will freeze to death during longer periods of frost, even if they are well protected. Instead, choose hardy or frost-hardy varieties, which are much less sensitive to stress from permafrost and fluctuating temperatures.

It depends on the climate zone

However, even the classifications "hardy" and "frost hardy" are no guarantee that your plants will survive the winter unscathed. After all, "winter" doesn't mean the same thing in every part of Germany. Germany is divided into a total of seven cold zones, whereby the lowest temperatures can vary quite a bit. So if a lavender plant can be safely left outside in wine-growing zones, it will hardly survive the low or strongly changing temperatures in some parts of Bavaria or on the coast. In this context it is important to know that hardiness and winter hardiness do not mean the same thing either. Frost-hardy plants survive quite well even longer periods with low temperatures, but hardly any strongly fluctuating climates.

Hardy varieties for the garden

This applies in particular to the hardy lavender, which may tolerate lower temperatures, but find it difficult to withstand strongly fluctuating temperatures. Lavender is used to a Mediterranean climate, which includes more or less constant climates than the drastic temperature drops and weather changes typical of parts of Germany. Therefore, you should also ensure that hardy lavender varieties are well insulated to protect the plants. Only the varieties of real lavender are considered hardy - and therefore suitable for planting out in the home garden. This comes from mountain regions between 600 and 1600 meters in altitude and is therefore more robust. The following varieties have proven themselves in German gardens:

  • Hidcote Blue
  • Munstead
  • Miss Katherine
  • Imperial Gem

However, this lavender should be planted in a sheltered, i. H. not in a draughty location, as the plants do not tolerate (strong) wind.

Which lavender varieties are not hardy?

All other lavender varieties are not hardy, although spike lavender and lavandin are at least partially hardy. However, these plants should better overwinter in a cold house, as should the French lavender, which is neither hardy nor winter-resistant. Wool lavender and fern-leaved lavender are also not suitable for wintering outdoors.

Overwinter hardy lavender properly

From autumn - ergo in September / October - you should cover planted lavender with brushwood or leaves if possible. Special insulating cold protection mats such as coconut or fleece mats are also well suited. This is especially true for the more delicate young plants, perennial lavenders are more robust in this regard. The cover not only protects the plants from the cold, but also from too much moisture - waterlogging is deadly for lavender even in winter. Therefore, you should only water when the ground is not frozen and the water can drain appropriately. If the lavender is covered with snow, you should definitely not remove it - the snow cover protects plants from the cold.

Don't prune lavender too late

Autumn pruning is part of the preparation for winter for many garden plants - but not for lavender. This can be pruned for the last time at the beginning of August at the latest, as the faded stems form a natural protection against the cold in winter. A later cut also robs the plant of its strength unnecessarily, since many varieties then start to flower again.

Beware of frost and sun

The sun can also be dangerous for the actually sun-hungry lavender in winter. Especially with temperatures around freezing point, the moisture from the leaves and soil evaporates faster on sunny days than the plant can absorb the water. In this case, the plant threatens to dry out, which is why you should regularly check it for signs of this and act accordingly. Lavender also doesn't like permafrost and then needs good protection from plant mats - especially when there is no snow.

tips and tricks

Potted lavender is always more susceptible than planted lavender, which is why different rules apply to this one. If the pots are going to be left outside (and may only be brought in briefly), you can wrap them in protective mats and cover the lavender itself with sticks.

IJA

Category:

Herbs