How Home Garden Pros Decide to Treat, Replace, or Tolerate Pests

With pests, my first approach is always to try to treat the problem. Pests, especially insects, can be pretty commonplace in gardens. That doesn't mean you should leave pests alone, but it does mean that you shouldn't just immediately resort to getting rid of the plants altogether. Try tackling the pest problem first with whatever method seems best according to the specific pest and plant. See how it works. If it doesn't work super well, you could try it again, or you could try a different method. Sometimes it may just take a few tries. If your efforts never end up working and you simply cannot save your plants from the pests, it's probably best to remove the plants altogether. If you want to replace them, make sure to replace them with plants that are in a completely different family so that the pests don't just get a brand new food source.

Decide whether to treat or replace a plant based on its current health, cost and the amount of work involved. If a problem is only slight but keeps coming back each year to stunt the plant's growth, replace the plant. Minor damage that does not affect yields is also OK to live with year after year.

One major loss of main roots or stems (the main framework of the plant) is my trigger point for pulling them and replanting. Plants generally don't regain full vigour after such damage.

My deciding sign is the condition of the newest growth, not the appearance of older damaged leaves. Healthy shoots after correcting water, airflow and soil stress suggest the plant can tolerate some damage. Use targeted treatment only after identifying the cause. Repeated stunting or dieback in new growth signals a failing plant-site match, making replacement more sensible than repeated treatment. Confirm unusual or spreading symptoms before removal because pest damage, disease and environmental stress often look alike.

Assess a few simple criteria: health of the plant in question, amount of overall damage, and additional time/effort you must devote to care of that plant. Treat minor problems with healthy plants that cause only mild damage. If pests are a yearly problem in a particular plant, replace it. Mild leaf damage to fruiting plants is usually acceptable as long as growth of fruit is otherwise healthy.

Guiding sign: replace the plant when leaf loss exceeds 50% of the total canopy, as it will likely remain weak and be unable to fully recover in subsequent years.

Isara Ongwiseth, lead designer, FormLA Landscaping
Bio: https://formla.com/team/isara-ongwiseth-2/

Often what looks like a maintenance problem is a design or installation problem. For example, failure to thrive can be an indicator that you have the wrong plant for the space. Maybe it's a sun plant trying to adapt to shade or vice versa. Sometimes there can be something unknown to you in the design or install phase. Underground hillside water flow can be tricky like that.

JT Wilkinson, maintenance care manager, FormLA Landscaping
https://formla.com/team/jt/

That's right. Also, pests are often temporary—patience can be way smarter than action. Of course, it could be a maintenance practice too: too much or too little water, mulch placed too close to the roots. If you like the plant, it's worth researching what it likes and seeing if adjustments are warranted.