With their characteristic needle shape and growth, the pines (bot. Pinus) are among the most popular conifers for many gardeners and are often integrated into the garden as a decoration. The wood supplier is known for the numerous, deep green needles that make the plant particularly attractive. However, pine maintenance can cause problems, eventually causing the needles to turn brown and the tree to lose them in large numbers.
All clear: age-related needle drop
Discoloration or shedding of the pine needles does not always have to be immediately caused by an illness. On average, a pine tree renews its foliage every three years to maintain vitality and a growth spurt. This depends on the following points:
- kind
- old
- health status
- location
Well cared for, older trees enjoy their pine needles longer, while a stressed specimen tends to drop their needles more quickly. However, this still has nothing to do with an illness. the natural needle case begins towards the end of summer with the oldest needle crops turning brown. Only a short time later, these fall off quite quickly in large bundles. However, the pine loses never complete their needlework, which is a sign of age-related needle fall. If your specimen suddenly suffers from dangerous needle drop and browning, it is one of the causes below.
Dwarf Pine, Mountain Pine, Pinus mugo
causes and treatment options
The following list gives you an overview of the typical diseases and pests that turn the pine needles brown until they finally lose them. Because pines extremely sturdy are growths, you can pep them up again with the appropriate treatment:
growth difficulties
These take place after relocation of pines that have been in one place for more than five years or are older than five years. Since many roots damage or tear off when transplanting, the pine stands under stress, resulting in yellow needle tips and then needle drop. The reason for this is the high water loss, since the roots need a long time before they can transport it again. The following steps will help you get your copy back in shape:
- Water the specimen continuously for half an hour
- Garden hoses work well for this
- water even when it rains
frost drought
The pine also does not tolerate drought in winter. In long periods without snowfall, the tree does not receive sufficient moisture and reacts with a loss of needles. It is therefore important to water sufficiently at such times:
- water regularly
- use cold water
- When the ground is thawed, pour directly onto the root disc
For potted plants, you need to fill the container with enough water to come out of the drainage holes. Besides, you should never de-icing salts Use near pine trees, as these can get into the roots via the dew water and over time turn the needles of the trees brown or yellow. The salt is just too aggressive for the conifers.
Soil compaction or desiccation
Pines should never be planted too close to walls or in soil that is too compacted. In combination with heavy rainfall, this can lead to waterlogging or when drying out lack of oxygen come. Check the location and soil of the pine for possible dryness or wetness. If this is the case, proceed as follows:
- Thoroughly rake soil around pine
- Work in compost (needle or foliage).
- per m²: 2 - 3 l
- finally mulch annually
- Bark mulch, compost, grass or leaves are suitable for this
Pinus sylvestris, Scots pine
calcareous chlorosis
As with many forms of chlorosis, the pH is not within the recommended range for the pine. If the needles turn yellow-brown over a long period of time, the soil is probably too alkaline and needs to be lowered. Pine trees prefer slightly acidic soil between 5.5 to 6.5 and react sensitively to higher values, since otherwise the iron in the soil can no longer reach the plant. You can lower the value accordingly:
- treat with iron chelate needles
- Dosage depends on the manufacturer's instructions
- or administer Epsom salt solution
- 10 g Epsom salt per 1 l of water
- Optimize fertilizer additions
- suitable fertilizers: conifer fertilizer, leaf compost (acidic)
Afterwards, only water the pine with rainwater or filter water, as it tolerates little lime.
scleroderris disease
This primarily affects black pines (bot. Pinus nigra) and mountain pines (bot. Pinus mugo) and is characterized by a clearly recognizable course of the disease. First, the pine needles turn distinctly brown, followed by the shoots, which turn reddish-brown to yellow. Over time, this affects the entire tree, which then has no chance of survival. This sac fungus must be combated as soon as possible because it is extremely contagious and can spread to other pines. Proceed as follows:
- Remove diseased parts immediately
- then burn
- do not throw in the compost
- Fungus can spread through air
- Contact the Föhren emergency service
If the infestation has progressed significantly, the tree must unfortunately be removed, otherwise the fungus can spread. So be very careful here.
Pinus parviflora, White Pine
pine moth
The pine moth (Bupalus piniaria) is one of the biggest pests for plants within the genus and is on the move from mid-May to late August. They choose the pine needles as a place to lay their eggs, because the larvae feed on them. As soon as the pine needles turn brown, they look gnawed and even caterpillars can be seen, use the following remedies:
- early stages: insecticides based on rapeseed or neem oil
- late stages: insecticides based on rapeseed oil or pyrethrins (chrysanthemum extract)
nutrient deficiency
With a prolonged lack of nutrients, the needles of pine trees turn brown, less often yellow, and over time they fall off. Make sure that the fertilizer used contains enough magnesium or, to be on the safe side, replace it with fertilizer for conifers.
tip: browning of pine needles can also be caused by spider mites, which can be recognized by webs resembling cobwebs. If this is the case, use classic home remedies and apply them at regular intervals.