The Life Cycle of the Spider Mite

Spider mites are a common agricultural pest. They inhabit the undersides of the leaves of many types of plants, feeding off of the sap. They will cause leaves to get mottled and eventually scorched, and can cause significant damage to affected plants. Spider mites, despite not being spiders, tend to weave webbing, hence their name. It looks noticeably different from regular spider webs, and is used for movement, protection, and keeping conditions dry. Their numbers can quickly increase if left unchecked, especially in their favored conditions, which is typically hot, dry weather. It takes work to wipe out a full-blown infestation, and understanding their life-cycle is very important for eradication.

Please read our dedicated article on how to kill spider mite eggs for specific removal information.


Spider mites lay many eggs that stick to the plant and/or webbing. A mature female mite is capable of laying several hundred eggs in total.

After hatching, they go through a larva stage and two nymph stages, before becoming a sexually mature adult. The length of the growth process varies by species and environment, taking anywhere from 1 – 3 weeks. A hot, dry environment will cause much faster growth and proliferation. Most mites are active during the summer months, but it should be noted that there are exceptions.

Some species prefer the cooler, humid conditions of spring and fall. They will reproduce during these seasons, and lay dormant eggs for the summer.All species will become dormant during cold winter months, either as hibernating adults or eggs.

Spider mites attack a wide variety of plants, but the cool weather mites focus on broad-leafed evergreens and conifers. So, those types of plants, along with herbs, should be checked during spring/fall. Other than that, summer is the main time to inspect your plants for infestation.


Spider mites are a sexual species with mating between males and females. Mated females lay eggs that hatch into females, while unmated females will produce males. This works because while female mites have two sets of chromosomes, males only have one. This also means that they are very adaptable to different conditions – they have been known to build resistance to standard pesticides, and rebound from decreases in population.


If you’re removing a spider mite infestation, your preferred method should work on all different growth phases of mites. However, eggs are smaller and sturdier. They can be laid in clusters or scattered around the webbing. They can lay dormant for extended periods. It can be difficult to kill or remove all the eggs.

One thing that can help is by releasing predators, as the spider mite’s natural predators eat eggs and mites alike. In general, you’ll need to administer multiple treatments to destroy an infestation, spaced out by several days, in order to complete your task and prevent any new generations from forming.

However, these predators can often become outnumbered by the “bad” mites and overpowered. To remove all eggs, one should purchase an organic spray such as LavaMite™.