Tomato Plant Not Growing Leaves? Stunted? This Is What Went Wrong…

Does your tomato plant seem to look a bit, lean, currently?

Are your tomato plant’s leaves growing slowly, or did your tomato plant seem to stop growing?

Tomato plants are incredibly easy to grow, but even the best of us have a few hurdles to jump in our gardening endeavors.

Here’s a list of all of your potential issues, no matter what your current growing environment is!

Tomato Plants Require Full Sun

If your tomato plants are not receiving full sun, they likely aren’t getting enough light. A plant that receives enough light tends to be shorter, stockier, and bushier, until begins to take off and flower.

If a plant isn’t receiving enough light, it may have a varying set of symptoms including:

  • Leggy stance and weakness (plant may have issues standing erect)
  • Plant may fall over easily
  • Flowering and fruit set is late and sparse
  • Plants will have fewer leaves that are smaller, with greater spacing
  • The plant may be lacking severely in growth rate, as compared to plants in sunny locations

Tomato Plant Is Under Attack By Pests

Several pests will attack tomato plants, with some of them defoliating the plant. You may even have losses of fruit, flowers, and entire stems.

One of the most notorious tomato pests is the tomato hornworm, the larvae of the Five Spotted Hawk Moth. This little critter can do a lot of damage, reducing a tomato plant down to something that resembles a leafless tree in mid-December.

Others may simply cause lots of holes in the leaves, leaf drop, or they may damage new leaves before they unfurl; meaning, you won’t see new leaves growing in as you should.

Check your plants for damage that correlates with:

  • Tomato Hornworms
  • Aphids
  • Cutworms
  • Flea Beetles
  • White Flies
  • Colorado Potato Beetles
  • Spider Mites

Tomato Leaves Are Dropping Due to Stress or Disease

Most plants will drop leaves or become stunted in growth when exposed to stress or disease. They conserve their energy, and are unable to thrive in unfavorable conditions.

Some examples of stress include:

  • Water Stress
  • Pest or Disease Induced Stress
  • Poor Soil
  • Heat Stress
  • Cold Weather

If you notice that you’re finding lots of leaves on the ground or a lack of fresh growth, take a moment to analyze your plant’s environment and its potential for being stressed. Too much rain lately? Did you experience a heat wave? Is this garden soil overworked or newly broken? Did you have a cold snap, or a recent battle with hornworms?

Disease is also another cause of leaf drop and stunted growth. Generally, you will see additional symptoms that accompany falling leaves:

  • Stunted growth
  • Discolored leaves
  • Wilting of leaves or branches
  • Lesions on leaves, branches, or fruits
  • Water soaked spots
  • Growths on the plant (may look like mold or sap)
  • A foul smell
  • Continual downhill condition
  • Potentially, neighboring plants become infected with similar symptoms

The Weather Is Not Favorable for Tomato Growth

Again, this circles back around to a stressed plant. However, we’re going to evaluate a few of these instances, so that you can understand them a bit more.

  • Hot Weather: Hot weather commonly causes plants to quit flowering or fail to fruit. However, you tend to still see plenty of foliage during this time, unless the heat is excessive (causing scalding, wilting, etc). Hot weather tends to be favorable for many pests, so you may see a significant increase in pest activity and damage. Thus, you may see some of your tomato plants suffering. We covered growing tomatoes in hot Tennessee weather in an earlier post, which may help you to successfully grow tomatoes in hot weather.
  • Cold Weather: Tomato plants do not like cold weather. If your temperatures are falling below 40*F, you may notice that your plants are slowing down significantly. You could try protecting them with sheets or blankets; tomato plants can and will survive these temperatures, but they do so reluctantly.
  • Wet Weather: In wet weather, bacterial and fungal diseases can run rampant. Viral ones can as well, due to rain water splashing viral particles up onto plants from the soil. The wet, humid environment is particularly favorable for fungal infections, which may result in a wide variety of symptoms (as we discussed above.)
  • Dry Weather: In dry weather, your tomato plants may begin to experience water stress. Most dry weather is favorable; however, an extended drought or heatwave will cause the soil to become far too dry, and it will wipe out the plant’s stored moisture, as well. The plant may drop leaves to conserve water and reduce transpiration.

Plants Are Overcrowded

If the plants are competing for light, they will not be filled out with foliage. Check the spacing between your plants. Remove any plants that are small and crowding the others in your garden.

If you remove plants, it may take a few weeks for the remaining plants to fill out and put on a beautiful set of leaves throughout their branches. Be patient, and you will have beautiful plants again!

Too Much Fertilizer, Too Early

Fertilizer is an excellent tool for ensuring that your plants receive everything they need to get a head start in life, grow adequately, and fruit prolifically.

However, too much of a good thing, can be a bad thing. Excessive fertilizer can cause plants to grow too quickly due to the excessive available nitrogen. This causes the plant to shoot up rapidly, rather than allowing the plant to grow as it normally would. It could become tall, spindly, and have sparse leaves.

Transplant Shock

If you have moved your plants into the ground in the last 30 days and have seen very little growth, it’s quite possible that they’ve gone through transplant shock.

Many people believe that transplant shock is worse or more drastic in appearance than what it is; sure, it could kill the plants. Seedlings may wilt.

But in most cases, it’s simply a temporary stressful event for the plant; it simply fails to thrive for 1 to 4 weeks, depending on the plant and the conditions that it is transplanted into.

To help the plant, be sure that you are offering it the conditions it requires to thrive (whether that be dry or moist soil, full or part sun, fertilizer, etc). Most plants will recover, and you will be able to identify plants that have successfully overcome transplant shock by their sudden new growth.

Scalding (Due to Sunlight, Etc)

Scalding tends to occur under one of three particular events:

  • Transplants were planted without hardening them off to sunlight, which causes scalding (it’s the same thing as a sunburn on a person.)
  • Plants are enduring very high temperatures under the hot sun in midsummer (not as common, but it definitely happens.)
  • Or, plants were watered or sprayed on a very hot day, with continuous exposure to direct sunlight.

Scalding usually appears as white or silver blotches on leaves, typically only on the leaves that are exposed to the most light.

Leaves may shrivel and drop after a few days if the damage was severe enough. It may take some time for the plant to replace those lost leaves, especially if the entire plant was affected.