In our part of the world, it is more normal than unusual for basil to develop black spots on the leaves. In the article you will find out how you can extend the life of the basil pots in the kitchen and that only basil of the right kind that you have grown yourself offers a real guarantee against “stain nuisance”.
Table of Contents
The possible causes
Don’t worry, you shouldn’t become a plant researcher for the sake of your basil – but a few ideas about the causes can help a lot in dealing with the problem. There are a few choices, but birch is a sensitive, warmth-loving Mediterranean plant that dislikes all sorts of things:
- No cold, whereby cold for a basil starts at around 15 ° C
- At temperatures below 12 ° C there is almost certainly damage, e.g. B. the typical spots on the leaves
- A basil can experience such low temperatures outdoors in summer
- Cold spots can also appear in hot midsummer
- Then the basil got its shock on the transport
- Staying in a dark truck that is much too cold can only have consequences much later
- Guilt can be incorrect pouring, or rather: normal pouring
- The delicate herb does not want to be poured or sprayed from above
- It could also be sunburn from too much direct sunlight
- Or a combination of both, water droplets can focus the sunlight
- Damp cool weather shocks a basil faster than the average German
- If there is also wind, the basil finally reacts “sniffed”
- All these conditions weaken, weakened plants like to be colonized by fungi
- Fungi and other weakness diseases can cause dark spots on the leaves
Save basil until final consumption
The pots are mass-produced in large nurseries: seeds suitable for turbo rearing grow under optimized lighting at optimal temperatures to the desired height and leaf mass at the time of sale. This basil is not produced to take a place in the herb garden over the summer. It is about “goods in pot storage” that are supposed to survive until the average customer has eaten the last leaf; a disposable product that stays fresh thanks to its roots and an almost earth-like substrate without any aroma-destroying cooling.
This form of sale does develop dark spots on the leaves quickly, but usually only if handled incorrectly; Even if you set up and care for the potty correctly, it can have a fairly long lifespan with fresh green leaves:
- Leave the foil on the pot to increase the humidity
- Place the basil in a light, warm room
- Better in partial shade than in full sun
- Basil on the balcony only thrives in sheltered, sunny locations without the midday sun
- And only when it’s warm day and night
- Always pour directly onto the soil in the root area
- Put the basil away from indoor plants that might spread mushrooms
- The film can be cut away cm-by-cm from above
- This allows the young plant to get used to the environment, but has more air against fungi
- Cut away leaf spots as soon as they develop or snap off infected leaves
- Water moderately but regularly and continue harvesting, maybe a few healthy leaves will follow
Brings long green, but many basil pots have already noticed their damage during the transport or in the supermarket (warehouse). If leaf spots develop, you can limit the damage by selective harvesting: leaves with dark spots can be eaten without any problems, they just don’t look so decorative anymore. They are therefore used in stews or in pesto, while the green leaves are adorned with mozzarella and tomatoes.
Help basil live longer without leaf spots
If you want a potty of basil from the grocery store to last you longer, there is a little more to do. Because the reasons just explained why basil is not only used by you at home, of course, also ensure that the basil does not grow any further (it shouldn’t at all; it should survive in the purchased form, but certainly not “for eternal self-renewal.” Mutate product “).
You have just acquired a very young seedling that has been forced into rapid, lean to lanky growth and has not yet had time to strengthen. On the contrary, the plant was rather well shaken during the transport, stood around somewhere in the cold or heat, saw hardly any light and even less (or suddenly an excessive amount) of water. First of all, a bit of rest and strength is called for before they help the young plant to grow better:
- Cut open the film at the bottom immediately after purchase and check the pot substrate
- Drain if the substrate is too wet
- Dip the dust-dry substrate (more often) into an immersion bath and allow it to drain
- Let the basil rest in a light, warm place for a day or two with foil
- Then free from the nutrient-poor commercial substrate
- Loosen the root area all around by pressing and pot the basil
- Depending on the amount of fine roots, place in one or more new pots
- Each root ball should only take up about a third of the pot in the middle
- Fill pots with loose garden soil or good, peat-free growing media
- Choose quality potting soil if you have bought soil (and not low-nutrient herb soil)
- Regularly provide a moderate amount of moisture, basil does not like waterlogging or dryness
- Always water from below, never on the leaves
- In early summer and summer like on the balcony
- Best in a sheltered corner with morning sun (and afternoon sun)
- The Mediterranean plant loves blazing sun, but only after acclimatization
- So, piece by piece, expose a little more to the sun
- If it is very hot, cover again with a foil hood, water more often (preferably in the planter, drain after 15 minutes)
- As a heavy eater, basil needs a lot of nutrients, in a pot it is best to use mineral-organic liquid fertilizer
If you give your basil this easy elaborate treatment, there is a good chance you will never see stains on the leaves. However, what should not tempt you to pluck the largest leaves all around during harvest, it takes away the desire to drift away from the delicate plant. It is better to pinch / cut off a whole piece of shoot above a leaf axil, then new shoots will grow out of the leaf axil, the plant will be bushier.
One restriction, however, cannot be ignored: basil pots are produced and sold as a food that, when properly treated, has an astonishingly long shelf life with a full aroma. But the shelf life of a fresh herb, which is measured in days even without “contamination by fungi or microbes” or whatever other conspiracy theory is circulating on the Internet, is measured in days.
Resistant green plants that can be kept for weeks or years, are grown under hardening conditions and sold in a nutrient-rich substrate, are available from gardeners and not in the supermarket – which is why we are now also coming to:
What really helps against stains on basil leaves
Supermarket basil can perhaps be persuaded to continue growing for a while with a lot of effort if late-acting previous damage does not thwart the bill, around 27 million! Basil pots are sold per year, felt not much less forum posts complain about received basil; In general terms, the high level of maintenance is not really worth it.
Instead of imposing an extended shelf life on a tiny portion of millions of basil pots through particularly careful care, which was not intended at all during production, it could make more sense to cultivate basil plants that are simply viable. You can buy them in the potty, too, but not in a supermarket. The company’s goal in the food retail sector is to supply the population with fresh food. This is the area in which the industry’s expertise and the strengths of the basil pots available there lie, they are even super fresh food. Rather, they would have to look for a company whose aim is to grow strong, resilient plants (which are prepared as well as possible for the German climate, if the plants are from Mediterranean regions).
You can also grow a long-life basil fresh from seeds; However, it is important to use the right seeds here. The pots in the supermarket are made from special seeds, bred for rapid growth, with the exception of resistance and lifespan. For pot culture for marketing as fresh produce, varieties of the ‘Genoveser’ type have prevailed, the “Descriptive List of Varieties of Medicinal and Spice Plants” lists the commercial varieties: Balkonstar, Bavires, Bubikopf, Genova, Genoveser, GenuaStar, Großes Grünes, Keskenylevelü, Lemon, Medium Leaf Greens, Pesto, Lettuce Leaf and Sanremo; you should avoid these seeds.
The safest way to get sensible seeds is to contact an ecologically working specialist gardener. There you can also get extensive advice, because there are not only more robust varieties of the mainly used basil type “Ocimum basilicum”, but also many different types of the basil genus, which have long been used as a spice in their homeland and today also in ours Are available.
If you want to grow basil yourself from seeds, you should forego the seed discs that have recently been offered “to simplify sowing”. They are usually filled with seeds of the sensitive commercial varieties, but cost many times more than normal organic seeds: 3.00 euros for 5! Seeds instead of 1.60 euros for 150 seeds (just so that you don’t have to put the seeds on the potting soil yourself). Such a basil in the bucket or in the summer garden, and you will get to know basil with flawless leaves – in an unusual size and with unusual vigor (not that easy to cultivate, but that is the next topic).
Conclusion
The basil with unsightly spotted leaves is not abnormal, but rather the rule. How you deal with the problem and what the chances are that your measures will work depends crucially on the type and origin of the basil. Only the self-grown basil will never develop black spots on the leaves with good care.