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Common growing problems

English
Star-flowered false Solomon's seal
Photo: Jardin botanique de Montréal (Michel Tremblay)
Maianthemum stellatum

Lack of light

Symptoms

  • New shoots are weak looking.
  • Growth is slow.
  • New leaves are smaller and turn pale.
  • Older leaves may turn yellow and fall.
  • Brightly coloured leaves turn green.
  • Plant fails to bloom.

Solution

  • Increase artificial or natural lighting at first signs of weakness.
  • Reduce room temperature by about 3°C.
  • Water less frequently and do not ferttilize.

Too much light

Symptoms

  • Leaves exposed to direct sunlight turn pale and develop faded spots that turn dry and brown.
  • Affected leaves turn increasingly pale.

Solution

  • Remove plant from direct sunlight in summer or install sheer curtains to filter light.
  • Remove badly damaged leaves.

Lack of water

Symptoms

  • Leaves wilt.
  • Growth is slow.
  • Brown spots appear on margins of older leaves, which eventually turn yellow and fall.
  • Soil is pale, hard and dry on the surface or damp on the surface and dry farther down.

Solution

  • Water plant.
  • If soil does not absorb water, immerse pot in a bucket of water until air bubbles stop appearing.
  • Remove pot from water and allow it to drain.
  • Continue watering at normal intervals.

Too much water or poor drainage

Symptoms

  • Leaves wilt.
  • Growth is slow.
  • Brown spots appear on leaf tips.
  • New and older leaves eventually turn yellow and fall at the same time.
  • Soil is constantly damp or drainage is too slow.
  • Roots become spongy, turn brown and rot.

Solution

  • Make sure that no water remains in saucer and place pot on a stack of newspaper for about one hour.
  • Return pot to saucer and allow soil to dry out before next watering.
  • Water less frequently.

Too much heat

Symptoms

  • Stems grow long and lanky (despite proper lighting).
  • Older leaves wilt (despite proper watering), turn brown around margins and fall.

Solution

  • Remove plant from direct sunlight in summer or heat sources in winter.
  • Check to see whether plant requires a rest period.
  • Remove badly damaged leaves to avoid disease.

Drop in temperature

Symptoms

  • Leaves are covered in white spots or turn yellow and drop a few hours after a sudden change in temperature.

Solution

  • Few indoor plants tolerate temperatures lower than10°C.
  • Keep an eye on plants kept outdoors in summer and protect plants transported outdoors in winter.

Lack of fertilizer

Symptoms

  • Young shoots are weak, smaller and paler (although not yellow) than rest of plant.
  • Flowers are faded or plant fails to bloom.
  • Plant is in an artificial potting mix and was not fertilized during the growing period.

Solution

  • Fertilize as recommended.
  • Transfer to a larger pot and add new soil, as necessary.

Too much fertilizer

Symptoms

  • Leaves turn brown and fall.
  • Plant stops growing.
  • Young shoots are sometimes deformed and blackened.
  • White crust forms on soil surface or pot rim.

Solution

  • Leach excess fertilizer salts from soil by flushing with water several times.
  • Fertilize less frequently and in smaller doses.

Salts accumulating in potting soil because of alkaline water

Symptoms

  • Leaf margins (especially on broad-leafed plants) or tips (especially on narrow-leafed plants) turn brown and fall.
  • White crust forms on soil surface or pot rim.

Solution

  • Let tap water sit for 24 hours before watering plants.
  • Mist aerial parts regularly.

Lack of humidity

Symptoms

  • Leaf tips turn brown.
  • Leaf margins turn yellow.
  • Flower buds dry out and fall.

Solution

  • Use a humidifier.
  • Mist plants regularly.
  • Remove them from heat sources.

Water used for watering is too cold

Symptoms

  • Small pale brown spots appear on leaves.

Solution

  • Some plants are very sensitive to sudden changes in temperature.
  • Use tepid water when watering.
  • Cold water may spot the leaves and slow the growth of some tropical plants.

Pot too small

Symptoms

  • New leaves are smaller.
  • Older leaves turn yellow and fall.
  • Plant wilts quickly between waterings.
  • Roots grow out of drainage holes or show near soil surface.

Solution

  • Confirm diagnosis by removing plant from pot.
  • Repot if roots form a tight ball.

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