Basil is probably one of the most important kitchen herbs and an important part of the Mediterranean cuisine. The royal herb is grown outdoors all year round in its original distribution area and enjoys sunny and warm temperatures that are hardly possible in Germany. Due to the popularity of the Ocimum species, many want to enjoy the fresh leaves all year round, but the question here is: is the spice plant hardy?
hardiness
Basil is not hardy
When winter sets in, Ocimum is often one of the first herbs to say goodbye to home gardens. The reason for this is the fact that no type of basil can really withstand temperatures below 10°C and sub-zero temperatures quickly and irrevocably lead to the death of the plant. Up to now it has not been possible to breed a hardy taxon and therefore it is important to get the kingweed through the winter with the right protection. The reason for the problem with basil and the cold season is the natural range of the genus, which is limited to the following regions.
- tropical Africa: most species of the genus are at home there
- tropical Asia
- South America
- Central America
- southern and south-eastern Europe: many species have been naturalized here
- tropical Australia
Red basil, Ocimum kilimanscharicum
origin
Not a single species of the genus actually comes from Europe. The classic royal herb (bot. Ocimum basilicum) is native to Africa and parts of Asia, especially India, where it is found together with the Indian basil (bot. Ocimum tenuiflorum) is even used for religious purposes. The tropical homeland suggests that the genus cannot cope with the winter temperatures in Germany. In order to make this point even clearer, the location requirements of the herb must be looked at.
- Light requirement: sunny
- warm with at least 12°C, otherwise the basil will not grow
- 20°C is ideal
- no rain
- no draft
These points apply to actually all types and varieties that are available on the market and that can be grown, especially in the warmer regions of Germany. Due to the need for sun and warmth, the royal herb is perfectly suited for keeping on the balcony or terrace, as the temperatures are often higher on these. Basil plants placed in front of a house wall are particularly lucky because they get a lot of sun and heat. While there are no hardy varieties of the plant, there are three hardy varieties of different species that can handle heavy rain.
- Basil 'Wild Crimson' (bot. Ocimum canum x basilicum 'Wild Purple')
- Camphor Basil 'African Blue' (bot. Ocimum kilimanjaricum x basilicum 'African Blue')
- Wild Basil, also called Tulsi (bot. Ocimum canum)
Basil, Ocimum basilicum
These three plants can easily be planted in regions in Germany that would otherwise be too wet. However, these are not hardy either, but they endure cooler temperatures a little better than the other taxa. This gives you more species and varieties that will thrive in your garden because of their resistance. They are even ideal for planting outdoors, while all other basil species grow better in a bucket or on the balcony than in a bed. However, overwintering the plants is not a problem with a little preparation.
Tip: The three types of Thai basil Horapa (bot. Ocimum basilicum var. thyrsiflora), Maenglak (bot. Ocimum citriodorum) and kaprao (bot. Ocimum tenuiflorum), like the three royal herbs mentioned above, are robust against rain. The aroma of the three types differs significantly from the classic kitchen basil.
preparation
In order for the royal herb to survive the cold season, some preparations must be made beforehand to make it easier to move to the winter quarters. If you don't have basil at home yet, you should first select one of the types or varieties that are suitable for cultivation in Germany.
'Genoveser' (bot. Ocimum basilicum 'Genovese')
- the classic type of basil and most commonly offered in Europe
Basilicum 'Pistou Provence' (bot. Ocimum basilicum 'Pistou Provence')
- small, round basil from France
Anise basil (bot. Ocimum basilicum 'Anise')
- the aroma is reminiscent of a mixture of aniseed and some pepper
Basil varieties 'Dark Opal', 'Chianti', 'Moulin Rouge', 'Purple Delight'
- are red-leaved and slightly different in aroma
Thai basil species
African basil (bot. Occimum kilimanscharicum)
- quite rare, contains aromatic camphor oil
In addition to these varieties and species, you should definitely try the following variants, as these are particularly efficient for cultivation in Germany and for overwintering.
- Basil 'Wild Purple' (bot. Ocimum canum x basilicum 'Wild Purple')
- Garden Basil (bot. Ocimum kilimanjaricum x basilicum)
- Russian shrub basil 'Gorbachev' (bot. Ocimum basilicum 'Gorbachev')
- African tree basil (bot. Ocimum gratissium x suave)
- Green-leaved African Basil 'African Green' (bot. Ocimum kilimanscharicum basilicum 'African green')
These species and varieties are the best perennial species that can survive the winter on the windowsill without any major problems. Since not all basil species grow perennial in Germany, you must be careful to choose a robust, perennial variant. The royal herb just keeps growing in the drops and is naturally perennial, but the extremely robust species are best grown in the local areas. These survive the darkness better than other varieties of the mint family (bot. Lamiaceae). If you grow your Ocimum in the bed, you should make the appropriate preparations for the winter.
Basil, Ocimum basilicum
1. Repot all of your basil plants into separate pots filled with the appropriate substrate. This should be as follows.
- nutritious
- humorous
- Garden soil or potting soil made from compost is a good choice for this
- fresh
- wet
- well drained
- Herbal soil should not be used because it is too lean
- pH: 6.5 - 7.5
The pots should have drainage holes and provide enough space for the plants.
2. Be sure to move the plants indoors as soon as the night temperatures drop to around 10°C to 12°C. This stops the growth stop that the plants suffer from these temperatures.
If you grow your royal herb in tubs or pots on the balcony or terrace, you only have to bring them into the living room when it is cold.
Tip: If you want to make it easier on yourself, you should plant the plant with the pot in the bed, because then you can simply dig it out of the ground before winter. It's even easier if the pot has handles that you can use to simply pull the container out of the ground and move it to the winter quarters.
Hibernation - instructions
When you have completed the preparations, there are a few things you need to consider when wintering. Of course, the temperature is particularly important, since the herbs depend on heat.
Proceed as follows for winter care:
1. The temperature throughout winter should be between 18°C and 22°C. It is necessary to place the Ocimum in a window seat or in the conservatory. The site should be as sunny as possible and preferably south-facing.
2. The chosen location must be protected from cold air, i.e. away from doors and windows that are frequently opened and closed. If this is not possible, you should build a protective structure, for example made of cardboard or a board.
3. Make sure that there is no waterlogging over the winter, this is dangerous for the plants.
Basil, Ocimum basilicum
4. Give the mints an organic-based liquid fertilizer at least every four to six weeks. This keeps the basil fit during the cold season.
5. A cut is not necessary over the winter, since the plant does not form flowers over the winter. But you can harvest the herb without any problems. Always cut whole shoots five centimeters long to stimulate growth.
Tip: if you cannot provide the plants with enough sunlight, you should switch to artificial light. Choose either special plant lamps with intensive LEDs or grow lamps with fluorescent light and shine on the plants for up to 12 hours a day.