Spider mites are pesky. They’re not insects, though they act and live like other insect pests. They’re more closely related to spiders and ticks than they are to insects.

These spider-like mites infest dry plants. They spin webs on leaves, stems, and flowers. Their tiny webs connect to form vast stretches of silky threads. You may notice the webs first before you see the microscopic mites.

Don’t worry if you do see their webs. They’re easy to remove, and many techniques prevent them from returning. Whether they’re indoors or outside, spider mites are harmful! Act quickly to combat fall spider mites, and invite predators that prey on them.

Epic Organic Garden Straw

Epic Organic Garden Straw

Olla Watering Kit

Garden Oya™ Watering Pot

Types of Spider Mites

There are many mites, and a select few feed on plants. Two main ones afflict garden specimens in the U.S., the spruce mite and the two-spotted spider mite. Watch for both on your conifers, vegetables, fruit trees, and nut trees. 

Spruce Mite

These mites are common on spruce plants.

Spruce mites inflict damage on conifers, like spruces, firs, junipers, Douglas firs, and dwarf Alberta spruces. They’re difficult to see with the naked eye; use a jeweler’s loupe or magnifying glass to see them.

Before seeing the mites, you’ll notice spotty leaves with yellow and bronze discoloration. They’ll die over time, and fine webs will appear throughout the conifer. 

These fall spider mites are more damaging to ornamental gardens than to vegetable plots and fruit orchards. They’re particularly harmful to wholesale conifer farms where many evergreen trees and shrubs grow close together. 

Two-spotted Spider Mite

These spider mites attack a variety of crops.

Two-spotted spider mite explosions are deadly for your crops! Coordinated efforts help combat them before their populations grow further. 

These fall spider mites are a tad larger than spruce mites, and they have two spots on their backs, as their name suggests. They target ornamentals, vegetables, and fruit trees. 

Drought-stressed plants are especially vulnerable to mite damage. Watch for yellow leaves, stippling, bronzing, and fine webs. 

Combat Fall Spider Mite Explosions

Don’t let those explosions get out of hand! Discourage them from occurring, and use targeted approaches to remove fall spider mites without harming beneficial pollinators and predators. Before grabbing the toxic pesticide bottle, consider these tactful methods. 

Water Regularly

Mites attack in dry conditions.

The thirstier your plant is, the more likely it is to submit to fall spider mites. Drought-stressed plants lack vigor, and their leaves are easy for the mites to puncture. Water the garden as often as necessary to keep your plants happy. 

Some plants require more moisture than others. Common crops, like tomatoes, peppers, and corn, are thirsty! They need more water than drought-hardy shrubs and perennials.

If you struggle with remembering to water, consider hooking up a hose to a sprinkler with an automatic timer. Set the sprinkler’s aim so the garden receives the water it needs. Then, program the timer so the sprinkler turns on in the morning or afternoon. 

Mulch Bare Soil

Add a thick layer of mulch to open areas.

A part of regular moisture control is regular mulching. Organic mulches break down over time. While they’re breaking down, they feed and protect plant roots. Mulches like compost inject beneficial organisms, like fungi and bacteria, to form intricate webs of life. 

The more alive the soil is, the more resistant it is to drought stress. Keep it covered at all times with a layer of mulch two to three inches thick. Water will stay below the layer, where worms and microorganisms convert organic matter into humus. 

If you don’t have compost, there are many mulch alternatives to combat spider mites in the fall. Fallen leaves are abundant and work well. Straw, coco coir, and wood chips are other alternatives. 

Promote Predatory Insects

Attract beneficial insects that feed on spider mites.

A long growing season ends in the fall, as temperatures cool and days shorten. It’s a perfect time to boost the garden with fall color from late-blooming flowers. Plant native plants to attract predators, and add flowering annuals and perennials to provide food for all insects. 

Predatory insects need shelter, food, and water to survive. Non-flowering plants, like ferns and conifers, are also beneficial! They provide nesting sites for wasps, predatory mite species, and spiders. Don’t worry; these predators won’t harm you, as they’re hungry for pests and not humans. 

Avoid spraying pesticides to prevent harming the predators. The fewer pesticides you spray, the more beneficial creatures will thrive. They’ll combat pests so you don’t have to worry about your flowers, crops, and fruit. 

Hose Off the Mites

If you spot fall spider mites, spray them off your plants.

Here’s the trick! Fall spider mites hate wet, humid conditions. They need dry, thirsty plant foliage to survive. Using a hose, you can spray them off daily or multiple times a day to dislodge them from your plants.

Repeated spraying is necessary to combat these pests in the fall. Don’t let up! Spray daily or more often wherever you notice mite damage. They’ll reproduce less, and you’ll knock the adults off the plants so they can’t feed further. 

Hosing off may not be the best method for certain crops in the fall. Squashes and grapes are susceptible to powdery mildew, and humid conditions may promote their growth. Consider the plant in question—if it tolerates spraying with water, spray it! 

Remove Infested Leaves

Get rid of highly infected plants.

If the fall spider mite explosion grows too large, remove the heavily infested leaves to save the rest of the foliage. The pests spread when they run out of food, and leaving infested foliage may promote their spread to nearby plants.

Don’t Spray Pesticides

These also impact beneficial insect populations.

Before grabbing the pesticide bottle, consider the damage it causes first! Broad-spectrum pesticides target many insects and mites, including pollinators and predatory insects. Without predators, fall spider mite populations experience explosions in growth.