Garden Troubleshooting Guide: How to Identify & Solve Common Garden Problems
If plants are struggling and not growing well, use this garden troubleshooting guide to help determine the problem and the possible solution.
Garden Troubleshooting Guide: How to Identify & Solve Common Garden Problems
Problem: | Often caused by: | Solutions to try: |
Plants are weak, spindly, pale and not growing well | Weeds: Weeds can choke out other plants and take sunlight, moisture and nutrients | • Pull weeds by hand before they set seed • If area is severely infested, consider solarizing area |
Plants are weak, spindly, pale and not growing well (cont.) | Poor soil | • Add good quality compost • Amend garden with a balanced organic fertilizer • Add worm castings • Add vermicomposting bins to beds • Add organic matter often to soil • Add vermiculite/perlite and coconut coir to increase water-holding capability |
Plants are weak, spindly, pale and not growing well (cont.) | Wrong growing season | • Plants have a preferred growing temperature; plant at the right time • If it is still hot, wait to plant cool-season crops • If it is still cold, wait to plant warm-season crops |
Plants are weak, spindly, pale and not growing well (cont.) | Lack of sunlight | • Move containers or raised beds to areas that get enough light • Reduce shade by removing trees, etc. • Thin plants – avoid crowding plants too close together • Plan your garden to avoid taller plants shading smaller plants; put trellises on the north side of your garden • Use a grow light when starting seeds indoors; keep light just a few inches from plants |
Problem: | Often caused by: | Solutions to try: |
Plants look dry around the edges and curl upward | Wind: Wind can be drying and stressful for plants | • Take advantage of natural windbreaks in garden planning • Add windbreaks; use poly tunnels or cloches for temporary wind protection |
Black spots, soft spots after a freeze | Frost Damage | • Remove the entire plant (annual) or wait until after danger of frost to cut it back (perennial) • Cover frost-susceptible plants during frost events |
Burned or yellow leaves and sunscald or burned fruit | Sun damage | • Provide shade during the hottest months of the year • Avoid planting sensitive plants in areas that receive afternoon sun • Harden off transplants before planting |
Yellow leaves, slow growth, brown dry lower leaves | Underwatering | • Increase watering • Use a moisture meter to get an accurate idea of soil moisture |
Plant wilts easily (Many plants in the Cucurbit family do this normally in the heat of the day; they usually perk back up as temps cool down) | Frequent, shallow watering builds fewer, shallower roots that don’t store as much moisture for the plant to use when it’s stressed | • Water the entire depth of your raised bed or container to encourage the roots to grow deep • Deep, healthy roots will provide moisture for the plant during the heat of the day |
Plant looks wilted and may have any or all of the following: • Wet soil • Brown leaves • Yellow falling leaves • New growth falling off • Floppy plant • Mold • Slimy or foul-smelling roots(root rot) | Overwatering | • Do not water again until the top inch or more of soil is dry • Remove flowers • Use a moisture meter to get an accurate idea of soil moisture. • Water only when soil is dry to the touch an inch or two below the surface |
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Garden Troubleshooting Guide: How to Identify & Solve Common Garden Problems (cont.)
Problem: | Often caused by: | Solutions to try: |
Light-green new growth with smaller leaves | Possible nitrogen deficiency | Feed with fish fertilizer if lacking nitrogen |
Red or purple leaves (that are supposed to be green) | Phosphorus deficiency | Feed with seaweed fertilizer |
White (bleached) spots on leaves of newly planted seedlings | Too much sun exposure | Harden off seedlings gradually |
Problem: | Often caused by: | Solution to try: |
Poor harvest | Plant does not produce desired harvest | • Choose varieties suited to climate (i.e., in the low desert, choose shorter days to harvest and heat-resistant varieties) • Plant at the correct time and temperature • Care for plant correctly – pay attention to plant each day • Plant in well-draining soil |
Cracked tomatoes, Splitting fruit & vegetables | • Irregular watering • Heavy rains | • Use an automatic timer, oyas, drip irrigation to water tomatoes • Tomatoes don’t like big fluctuations in soil moisture • If a large amount of rain is expected, harvest fruit prior to the rain |
Bolting plants (central stalk forms and develops a seed head) | Plant switches from food production to seed production | Temperature extremes (usually too hot) |
Powdery mildew (a white, powdery-looking substance on leaves; usually begins as small white spots on the top of leaves and spreads) | • Water on leaves • Not enough sunlight or airflow • Humid, wet conditions | • Remove affected leaves • Move the container to a sunnier location • Prune overcrowded branches or plants to increase air circulation • Spray plants with a solution of 1 tsp baking soda or potassium bicarbonate and castile soap mixed with 1 quart water • Remove heavily-infected plants |
Tomatoes won’t ripen | Too hot, too cold | • Top plant by removing cutting central stem. • Remove suckers, blossoms, and diseased leaves • Smaller tomatoes will ripen faster • Harvest fruit as soon as it flushes color (it will finish indoors) • Cover plants at night when temperatures are below 50°F • Move the container to a sunnier location |
Garden Troubleshooting Guide: How to Identify & Solve Common Garden Problems (cont.)
Problem: | Often caused by: | Solutions to try: |
Lack of pollinators and beneficial insects | • Pesticide use • Lack of flowers, herbs, diverse plantings | • Do not use pesticides • Use organic controls sparingly • Plant a variety of vegetables, flowers, and herbs • Allow herbs to flower • Interplant different types of crops throughout your garden • Grow flowering plants that provide nectar and pollen |
Seeds won’t germinate | • Not enough time has passed • Poor seeds • Seed dried out • Wrong temperature (too hot or too cold) • Soil is too wet • Birds / slugs ate seeds | • Do not allow newly-planted seeds to dry out • Use garden markers to mark newly-planted areas • Start indoors or in containers, and then transplant • Use fresh seeds • Use barrier methods to prevent seed loss from animals and birds • Start seeds indoors under controlled conditions |
Diseases | Planting crops in same location each year | • Rotate different crop families – try to allow 2 years between planting the same family of crops • Alliums: garlic, onions, chives • Amaranths: beets, chard, spinach • Asters: lettuce, sunflowers, chamomile • Brassicas: broccoli, cabbage, cauliflower, kale, kohlrabi, radish • Cucurbits: squash, cucumber, melon • Mint: basil, mint, rosemary, sage • Legumes: beans, peas • Nightshades: tomatoes, peppers, potatoes, eggplant • Umbels: carrots, celery, cilantro, dill, parsley |
Problem: | Often caused by: | Solutions to try: |
Diseases (cont.) | Planting crops too close together | • Plants need sufficient airflow to be healthy • Plants that touch each other are more likely to have problems with diseases |
Diseases (cont.) | Overwatering | • Many fungal diseases are caused by too much water in the soil or on the plant’s leaves • Plant in well-draining soil |
Diseases (cont.) | Lack of sunlight | Most plants need at least 6-8 hours of sunlight to be healthy |
Damage to plants | Rodents | Traps, cats |
Damage to plants (cont.) | Birds | Bird mesh, barrier methods |
Damage to plants (cont.) | Insects | • Barrier methods, organic gardening methods, beneficial insects • Various treatments and causes • See the article, “Organic Pest Control That Really Works”, for pest identification and treatment options |
Problem: | Often caused by: | Solutions to try: |
Blossom end rot (a brown, leathery rot developing on or near the blossom end of tomatoes, peppers, etc.) | • Irregular watering • Improper soil pH • Lack of calcium | • Maintain consistent moisture levels throughout season • Cold soils limit nutrient uptake • Apply mulch to prevent moisture loss • Apply a fertilizer higher in phosphorus • Maintain soil pH at or near 6.5 |
Damping off (Fungal disease that causes the stem to rot and kills seedlings) | • Crowded seedlings • Overhead watering | • Use sterile potting mix • Grow in well-drained soil with plenty of light • Do not crowd seedlings • Water from the bottom • Thin layer of sand, perlite, or sphagnum moss on the top of the soil • Use a fan to circulate air |
Squash, cucumbers, etc. not forming fruit (plenty of flowers, no fruit) | Lack of pollination | Hand pollinate: • Best done early in the morning • Remove the male blossom; pick off or pull back the petals and rub the stamen against the pistil of the other flower • Alternatively, use a cotton swab to transfer the pollen from the male flower to the female flower |
Hi! I would love your expertise! I live in Scottsdale. I am working on my spring salsa garden, and found a handful of grubs in my four foot square garden. I also have a few plants, peppers and tomatoes, that are spindly and not growing or producing well. Is this because of grubs? What should I do? Do you suggest nematodes, or milk spores?
Dig down and remove any grubs you can find. Those warm-season crops should begin growing well as temperatures warm up (nighttime temps above 50°F).
Hi, I love everything you teach. I have learned so much. I do have a question. I live in Tucson and i have two problems in our garden, 1: ground hogs, 2 tree roots.
The ground hogs burrow and get into the planter boxes from underneath and eat the plants. The trees (we have 6 mesquites ), last year, their roots totally invaded the raised garden. I have since lined the bottom with 3 layers of cardboard with new soil. But is there a good solution to keep roots and critters from entering the raised gardens from the bottom?
You’ll have to put barrier methods (hardware cloth, etc) in place before you fill with soil. I have a blogpost about how to trap ground squirrels coming soon.