Are your plants looking a bit less than stellar right now?
Heat, wind, and smoke pollution are all contributing to the mid-summer plant slump in our gardens. Our perennials and veggies aren't looking their best and don't seem to be growing as fast or blooming as often.
Showing stress this time of year is common for outdoor plants. Several factors contribute to plant stress:
Heat Stress/High Temperatures and/or Sunburn
Excessive heat causes plants to lose water through transpiration, leading to dehydration and reduced growth. Intense sunlight can damage leaves, causing scorching or sunburn.
Poor Watering Habits
Inconsistent watering or prolonged drought can lead to dry soil and stress plants, impacting their health and growth. Conversely, overwatering can lead to root rot and poor oxygenation, stressing plants as well. Check the soil moisture at least 6 inches down with a moisture meter before giving the plant more water.
Nutrient Depletion
By mid-summer, plants may have depleted the nutrients in the soil, leading to deficiencies that can affect their growth and appearance. Regular feeding may help to replenish nutrients and support continued plant health (see tip box below regarding fertilization).
Pest and Disease Pressure
Summer often brings an increase in pests and diseases (hello grasshoppers and blister beetles, aphids and hornworms), which further stresses plants and causes visible damage.
Physical Stress
As plants grow, they may become overcrowded, leading to competition for light, water, and nutrients. Some plants may become top-heavy or structurally weak, leading to drooping or other physical issues.
Natural Growth Cycles
Some plants naturally have a slower growth phase during the hottest part of the year, as they might slow down growth to conserve resources.
What to do
Showing stress this time of year is common for outdoor plants. Several factors contribute to plant stress:
Heat Stress/High Temperatures and/or Sunburn
Excessive heat causes plants to lose water through transpiration, leading to dehydration and reduced growth. Intense sunlight can damage leaves, causing scorching or sunburn.
Poor Watering Habits
Inconsistent watering or prolonged drought can lead to dry soil and stress plants, impacting their health and growth. Conversely, overwatering can lead to root rot and poor oxygenation, stressing plants as well. Check the soil moisture at least 6 inches down with a moisture meter before giving the plant more water.
Nutrient Depletion
By mid-summer, plants may have depleted the nutrients in the soil, leading to deficiencies that can affect their growth and appearance. Regular feeding may help to replenish nutrients and support continued plant health (see tip box below regarding fertilization).
Pest and Disease Pressure
Summer often brings an increase in pests and diseases (hello grasshoppers and blister beetles, aphids and hornworms), which further stresses plants and causes visible damage.
Physical Stress
As plants grow, they may become overcrowded, leading to competition for light, water, and nutrients. Some plants may become top-heavy or structurally weak, leading to drooping or other physical issues.
Natural Growth Cycles
Some plants naturally have a slower growth phase during the hottest part of the year, as they might slow down growth to conserve resources.
What to do
- Watering: Ensure consistent and adequate watering, but avoid overwatering. Water deeply but less frequently, and spread mulch to retain moisture.
- Shade: Provide shade during the hottest part of the day if possible, to protect plants from excessive heat and sun exposure. This could be as simple as placing a shade cloth lightly over plants in a particularly hot area of your garden.
- Fertilizing: Apply a balanced fertilizer or compost to replenish soil nutrients.
- Pest Control: Monitor for pests and diseases regularly and address any issues promptly.
- Pruning: Remove any dead or diseased foliage to improve air circulation and plant health.
Important note about fertilizing: Veggies and other annual plants in the garden and pots will benefit from fertilizer late into summer. According to CSU Extension, fertilizer is best used on plants at their peak growing cycle, just before flowering or leafing out. With plenty of moisture, plants can continue to take up fertilizer during their growing season, but discontinue by Fall.