Prolonged drought is a significant environmental stressor that negatively impacts plant growth, development, and survival. Drought in early spring when water for growth is critical has the greatest impact on plant health and survival.
The symptoms of drought stress in plants are varied and can range from subtle changes like wilting and leaf discoloration to severe consequences of reduced growth, stunted development, and even death.
The primary cause of prolonged drought is a lack of precipitation, which can be exacerbated by factors such as climate change, deforestation, and unsustainable agricultural practices. At Atlanta Arbor, we have treatments and procedures to help mitigate the drought stress on trees.
What is drought?
Drought is a period of drier-than-normal conditions that results in a water shortage. It is a deficiency of precipitation over an extended period (usually a season or more). This can happen due to below-average rainfall or even normal rainfall levels coinciding with increased evaporation rates. Drought stresses plants, making it difficult for them to grow and function properly.
Prolonged drought significantly impacts plant growth and development by reducing leaf size, stem extension, and root proliferation, disturbing plant water relations, and reducing water-use efficiency. According to Farooq, M., Wahid, A., Kobayashi, N., Fujita, D., & Basra, S. M. A. (2009). Plant drought stress: effects, mechanisms, and management. Agronomy for Sustainable Development, Plants display a variety of physiological and biochemical responses at cellular and whole-organism levels towards prevailing drought stress, thus making it a complex phenomenon.
What are the signs and symptoms of drought stress on plants?
The signs and symptoms of drought stress on plants include leaf rolling, wilting, yellowing, and leaf scorching. Plants may also develop early fall color or burning or scorching on their leaves. Additionally, a grayish cast to leaves, leaf curling or rolling, and drooping leaders on conifers are common signs.
Here are six signs and symptoms of drought on plants:
- Wilting and drooping leaves: This is one of the most common signs of drought stress. When plants don’t have enough water, their leaves will start to wilt and droop. This is because the plant is trying to conserve water by reducing its surface area. In the early stages, leaves may perk up at night, but as drought progresses, wilting becomes permanent.
- Leaf curling or rolling: Leaves may curl or roll inwards in an attempt to reduce water loss through transpiration. This is a way for the plant to conserve the little moisture it has left.
- Yellowing or browning leaves: As drought stress worsens, leaves may start to turn yellow or brown. This is because the plant is breaking down chlorophyll, the pigment that gives leaves their green color, to conserve resources. Eventually, the leaves will die and fall off.
- Stunted growth: Plants that are not getting enough water will not grow as quickly as they should. New leaves may be smaller than usual, and overall growth may be stunted.
- Reduced flowering and fruiting: Drought stress can also affect a plant’s ability to flower and fruit. Flowers may be smaller or fewer in number, and fruits may be underdeveloped or ripen prematurely.
- Increased susceptibility to pests and diseases: Plants that are under drought stress are more susceptible to pests and diseases. This is because they are already weakened and less able to defend themselves.
If you see any of these signs of drought stress on your plants, it’s important to take action to water them deeply. You should also try to conserve water by mulching around your plants and watering them early in the morning or evening when temperatures are cooler.
Atlanta Arbor understands the challenges posed by drought conditions and their impact on tree health. We offer various treatments and procedures to help alleviate drought stress and promote tree resilience.
What are the Effects of a prolonged drought on plants?
The effects of a prolonged drought on plants are stunted growth, reduced root system development, impaired photosynthesis, and increased susceptibility to pests and diseases.
Here are four key effects of prolonged drought on plants:
- Plant Growth
Prolonged drought significantly affects plant physiology, restricting growth and vitality. This manifests as stunted chlorotic leaves, premature defoliation, crown thinning, bark splitting, and poor shoot growth. Plants experience reduced growth due to limitations on cell division and expansion. Drought stresses plants, hindering their ability to take in water and nutrients, leading to stunted growth, smaller leaves, and reduced production.
- Plant Root Systems
To conserve water during a drought, plants may prioritize root growth over above-ground growth. However, dry soil conditions can make it difficult for roots to penetrate deeply and access available water resources, further stressing the plant.
- Photosynthesis
Photosynthesis, the process by which plants convert sunlight into energy, requires water. During a drought, limited water availability can hinder photosynthesis, reducing a plant’s ability to produce the food it needs to survive and grow. Water stress also causes the translocation of essential materials like carbohydrates and proteins throughout the plant, further weakening its overall health and resilience.
- Plant Pests and Diseases
Drought-weakened plants are vulnerable to pests and diseases, with insects and fungal pathogens being particularly attracted to stressed plants. Insect pests like borers and bark beetles, along with fungal diseases such as cankers and root fungi, tend to target trees experiencing drought stress, hastening their decline and potentially leading to their demise.
How to minimize the symptoms and effects of prolonged drought on plants?
To minimize the symptoms and effects of prolonged drought on plants, strategies such as increasing water availability through proper irrigation and mulching are essential. Enhancing water retention through soil amendments, selecting drought-tolerant plant varieties, and optimizing plant density for reduced competition are essential.
Here are five ways to manage the symptoms and effects of prolonged drought on plants:
- Water Conservation and Management
To mitigate the effects of drought on plant growth, it’s essential to conserve water and manage it efficiently. This can be achieved by:
- Watering plants deeply but infrequently to encourage deep root growth and reduce transpiration.
- Mulching around plants to retain moisture and reduce soil temperature.
- Using drip irrigation or soaker hoses to deliver water directly to the roots, reduces evaporation and runoff.
By conserving water and managing it efficiently plants can continue to grow healthily even in drought conditions. This is especially important for plant root systems, which need consistent moisture to develop properly.
- Soil Improvement and Fertilization
Healthy soil is crucial for plant growth, especially during drought. To improve soil health, gardeners can:
- Add organic matter like compost to improve soil structure and water-holding capacity.
- Fertilize plants with a balanced fertilizer to promote healthy growth and development.
- Check soil pH and adjust if necessary to prevent nutrient deficiencies.
By improving soil health, plants can absorb water and nutrients more efficiently, reducing the impact of drought on photosynthesis and overall plant health and growth.
- Pruning and Training
Pruning and training plants can help reduce water loss and promote healthy growth. This can be achieved by:
- Pruning plants to reduce transpiration and promote bushy growth.
- Providing support for plants to prevent drooping and wilting.
- Training plants to grow in a way that reduces water loss and promotes healthy growth.
By pruning and training plants, gardeners and homeowners can reduce the risk of wilting and drooping leaves, leaf curling, and yellowing or browning leaves.
- Pest and Disease Management
Drought-stressed plants are more susceptible to pests and diseases. To manage pests and diseases, gardeners can:
- Monitor plants regularly for signs of pests or diseases and take prompt action.
- Use organic or integrated pest management (IPM) methods to minimize harm to beneficial insects.
- Remove weeds that harbor pests and diseases.
By managing pests and diseases, gardeners or homeowners can reduce the risk of increased susceptibility to pests and diseases, and promote healthy plant growth.
- Environmental Modification
Modifying the environment around plants can help reduce the impact of drought. In the garden, this can be achieved by:
- Providing plants with full sun to partial shade, depending on their requirements.
- Improving air circulation around plants to reduce humidity and prevent disease.
- Avoid exposing plants to extreme temperatures or sudden temperature changes.
You may also be interested in our other articles such as:
Top 10 Causes of Tree Discoloration and Poor Growth
How to plan a drought-resistant garden?
To create a drought-resistant garden you can start by selecting native plants that need little water, reduce lawn area, mulch with wood chips or compost, and consider drip irrigation for efficient watering and more!
Here’s a guide to help you create an effective drought-resistant garden:
Assess Your Site
Before designing your drought-resistant garden, it’s essential to understand your local climate and the specific challenges regarding water availability. Test your soil for type and drainage, as sandy soils drain quickly and may need more organic material, while clay soils retain moisture but may require better drainage.
Select Native and Drought-Resistant Plants
Opt for plants native to your region, as they are adapted to local conditions. Look for plants known for their drought resistance, such as succulents like aloe, agave, and sedum, perennials like lavender, yarrow, and Russian sage, trees and shrubs like juniper, manzanita, and sagebrush, and grasses like blue fescue and buffalo grass.
Plan Your Layout
Create a water-efficient layout by grouping plants with similar water needs together in hydrazones. Take advantage of natural microclimates in your garden, where certain areas receive more shade or retain moisture better. By placing plants in these areas, you can create a more efficient and water-saving layout.
Soil Preparation
Improve your soil by adding organic matter to enhance its structure and water retention. Apply a thick layer of mulch (2-4 inches) to conserve moisture, reduce soil temperature, and suppress weeds.
Efficient Irrigation
Install a drip irrigation system to provide water directly to the plant’s root zone, reducing wastage. Water early in the morning or late in the evening to minimize evaporation. Consider using rain barrels to collect and store rainwater for your garden.
Maintenance Practices
Keep weeds in check, as they compete with your plants for water. Regularly prune plants to reduce water loss and promote healthy growth. Continuously monitor the garden for signs of stress and adapt your water practices accordingly.
Can plants recover from drought without any care?
Plants can sometimes recover from drought without care, but it depends on the plant species, its overall health, and the severity of the drought. Some plants, like succulents and cacti, are naturally drought-tolerant and can survive extended periods without water.
However, most plants will need some form of assistance to recover, such as watering and providing nutrients. The length and severity of the drought are perhaps the most important factors influencing plant survival. The most critical period for plant health and survival is early spring when water is crucial for growth. During this time, drought can have a devastating impact, potentially leading to plant death.
Can drought benefit plants that produce flowers?
Drought can benefit plants that produce flowers by accelerating their flowering time, enabling them to complete their life cycle before the onset of severe drought.
According to Basu, Supratim et al.’s (2016) article “Plant adaptation to drought stress”, published in F1000 Research, some plants exhibit a drought escape mechanism, where they rapidly flower and produce seeds before the soil moisture depletes. This strategy allows them to avoid experiencing the full effects of drought stress. Plants with this adaptation are considered to have little to no specialized morphological, physiological, or biochemical adaptations for drought resistance.
Another study done by Zia, Rabisa et al.’s 2021 article ‘Plant survival under drought stress: Implications, adaptive responses, and integrated rhizosphere management strategy for stress mitigation’, mentions drought stress can lead to an increase in flowering time for certain plants, allowing them to reproduce before the drought becomes too severe.
How do plants survive drought?
Plants have three main strategies to survive drought: escaping, avoiding, or tolerating the loss of water. Drought-resistant plants can escape drought by completing their life cycle quickly during wet periods. They can avoid drought by conserving water through adaptations like deep roots or waxy leaves. Tolerant plants can survive drought by adjusting their metabolism to cope with water stress.
What plants can survive drought?
Plants such as Coneflower, Catmint, Agastache, Lantana, Salvia, Lavender, Russian Sage, California Poppy, Aloe, Aster, Beardtongue, Black-Eyed Susan, Yarrow, and Acacia are known for their drought tolerance. These plants can handle dry weather and require minimal watering. Additionally, Yuccas and Cotyledon orbiculata are also low-maintenance plants that thrive in full sun and well-drained soil.
