Zucchini leaves turning yellow

My Cucumbers Leaves are Turning Yellow & Dying

Unless you’re a superhuman who happens to garden as well, you’re more than likely to wake up one morning and realize that some of your vegetable leaves have turned yellow. If your cucumbers leaves turning yellow you might have a problem.

Don’t panic – this happens to the best of us! Next, you might be wondering why it happened. I am here to clear that issue up and help you correct it.

Having had my fair share of failed vegetable gardening I consider myself somewhat a pro when it comes to fixing these types of problems.

Why does this happen?

The first issue we need to clear out is why it happens. I’m going to focus on cucumbers specifically for this article. Cucumber leaves can turn yellow for various reasons.

Some of them are water levels, light, pests, disease or a potassium, iron or nitrogen deficiency. Once you’re able to determine what is causing your cucumber leaves to turn yellow, you can figure out what to do about it.

Water levels

This is probably the easiest problem to solve. Just water less or more. If you get stuck at this step, read through guides like these to help you determine how much water your plants need.

You can also make use of to handy gadgets help you measure the moisture in your soil and prevent you from over – or under watering your plants.

Getting this step wrong can cause leaves to turn yellow without any other harmful factors being present.

Light

Cucumber plants love sunlight! If your plants aren’t in the sun long enough, no amount of water or nutrients will help it grow.

Cucumbers need at least 6 hours of sun per day, but some might enjoy 8 hours better. Whether you’re growing your cucumbers under artificial light of making use of the good old sun, you need to make sure that they are getting enough of it.

Pests and Disease

If you’re dealing with pests you need to determine which they are. Common pests that love to feed on cucumber plants and leaves are potato leafhoppers, aphids, spider, mites or whiteflies.

These pests can all be treated by using prepared insecticidal soaps or removing leaves from the bottom of your plants. Other methods are also available and reading up on them is always a good idea!

Treating diseases on your cucumber plants is a whole other story. The Mosiac virus and verticillium wilt are spread by pests or found in the soil as a result of previous crops.

Unfortunately, there is no way to treat these two common diseases. To my shock, I found that you need to remove your infested plants as soon as possible to prevent the diseases from spreading.

You will also have to be wary of planting in that soil the next season since these diseases can keep infecting for up to a year!

Some other diseases are easier to treat. If you notice white powdery spots and coating on your cucumber leaves, it is only a fungal spore and picking off the infected leaves as well as not overwatering will clear up this problem.

Yellow and brown spots indicate downy mildew. Improving air circulation and keeping your garden free of debris will solve this problem.

Deficiencies

Deficiencies can each be treated in their own way. That’s why you’ll need to determine which deficiency is making your plant leaves turn yellow. I decided to break each common deficiency down for you.

Nitrogen deficiency can be cured by buying soil fertilizer that uses the proper dilution rate. Even a slight mishap here will damage your cucumber plants. Using organic fertilizers work best in my experience.

Potassium deficiencies are caused by excess calcium, sodium or nitrogen, so you need to feed your plants with organic nutrients that are right for the growth stage in which the plants find themselves. During the flowering stage, this potassium need tends to be higher.

For iron deficiencies, you can either treat the plant or treat the soil – doing both is a bonus, but remember that balance is key.

Liquid iron can be sprayed on plant foliage, although this isn’t a lasting solution. To treat soil, you can use either powdered or granular chelated iron that you’ll have to sprinkle around the root zone.

Growing a vegetable garden and being able to harvest your crops is a very rewarding feeling! I am big on gardening and nothing gets me under as fast as dead plants.

Educating yourself on what causes this and how to fix it is the best thing you can do for yourself and your garden.

Whether you garden like they did in the old days or make use of modern gadgets to help you along, a harvest ready crop equals a happy gardener and in the end that is all that matters. These are the reasons why cucumbers leaves turning yellow.

Sources and References:

  • How to Water Cucumbers – homeguides.sfgate.com
  • Help! Why Are My Cucumber Plants Turning Yellow? – gardenloka.com

  • Why are my plants turning yellow? – mnn.com
  • How Much Sun Does a Cucumber Plant Need? – homeguides.sfgate.com

Cabbage family crops that share similar soil pH requirements growing together.

Vegetables and other plants grow best when the soil pH is optimal for the plants being grown. It is important to match a plant to the soil pH or to adjust the soil pH to a plant’s needs.

Soil pH is the measure of the soil’s acidity or alkalinity. Soil acidity and alkalinity is measured on a scale of 0 to 14, called the pH scale. Most plants grow between the pH range of 4.5 to 8.0; a soil pH of 5.0 has a high acid content; a soil pH of 7.5 has a high alkaline content; a soil pH of 7.0 is neutral. A soil pH test will determine a soil’s pH.

Soil pH is important because a soil’s acidity or alkalinity determines what plant nutrients are available to plant roots. Nutrients in the soil—elements such as nitrogen, phosphorus, and potassium—become available to plants when they dissolve in water or soil moisture. Most plant nutrients will not dissolve when the soil is either too acidic or too alkaline.

Knowing the soil pH in the planting beds in your garden will allow you to group plants by their pH needs. Grow together plants with like pH needs, similar temperature tolerances, and nutritional needs.

Crops Listed by Soil pH Requirements:

This list will allow you to group plants according to their soil pH tolerances. You will find that in the lists below, some plants may be repeated if they have a wide soil pH range tolerance; that is some plants will grow equally well in acid or alkaline soil.

Acid Soil Crops: The following crops prefer a pH of 4 to 5.5:

  • Blackberry (5.0-6.0)
  • Blueberry (4.5-5.0)
  • Cranberry (4.0-5.5)
  • Parsley (5.0-7.0)
  • Peanut (5.0-7.5)
  • Potato (4.5-6.0)
  • Raspberry (5.5-6.5)
  • Sweet potato (5.5-6.0)

Somewhat Acid Soil Crops: The following crops prefer require a somewhat acid soil; they can tolerate a pH of 5.5 to 6.5:

Moderately Alkaline Soil Plants: The following crops will tolerate a pH of 6.0 to 7.0 or greater:

Very Acid to Alkaline Soil Tolerant Plants: The following crops have the greatest tolerance for a wide range of soil acidity or alkalinity, from about 5.0 to 7.0:

Click on These Related Articles on Soil pH:

Understanding Soil pH

How to Test Your Soil

Adjusting Soil pH

Oregon Vegetables

Cucurbita pepo

Last revised February 12, 2010

Summer squash is defined as fruit of the Cucurbitaceae family that are consumed when immature, 100% of the fruit of which is edible either cooked or raw, once picked is not suited for long-term storage, has a soft rind which is easily penetrated, and the seeds of which would not germinate at harvest maturity: e.g. Cucurbita pepo (i.e. crookneck squash, straightneck squash, scallop squash, zucchini, vegetable marrow).
Other genera in the Cucurbitaceae family whose fruit may be consumed when immature include Lagenaria spp. (i.e. hyotan, cucuzza); Luffa spp. (i.e. hechima, Chinese okra); Memordica spp. (i.e. bitter melon, balsam pear, balsam apple, Chinese cucumber); and other varieties and/or hybrids of these. Production practices for all these species are similar to those described below for summer squash.

Summer Squash. Photo credit: Bill Mansour, Oregon State University

VARIETIES

See the Vegetable Variety Selection Resources page to find varieties that have been shown to perform well in the Pacific NW.

Vegetable Sponge, Dishcloth gourd, Sponge gourd (Luffa sp.). These may be used for cooking when immature (approximately 75 days), or allowed to mature for the fibrous spongy tissue (approximately 115 days): Angular types (Luffa acutangula): San-C, Ping-Ann. Cylindrical types (Luffa aegyptica): Cylinder, Seven Star, Seven Beauty. These produce higher quality sponge fiber.

SEED AND SEED TREATMENT

Zucchini and most summer squash seed number approximately 200-300 per ounce. Use fungicide-treated seed. Summer squash seedlings are susceptible to damping off and decay when soils are cool and wet.

SOIL TYPE AND TEMPERATURE

Zucchini grows best on fertile, well-drained soil supplied with organic matter. The ideal pH for zucchini growth is between 6.0 to 7.5, but it will grow on soils with a pH of up to 8.0. Consult a soil test for fertilizer and liming recommendations.

The minimum soil temperature required for germination of zucchini is 60 F, with the optimum range between 70 and 95 F.

SEEDING

Zucchini are usually direct-seeded when all danger of frost has passed. In western Oregon planting begins in early May and extends to mid-July. Stagger plantings 10 to 14 days apart to maintain a continuous supply of high quality product.

Use 36 to 40-inch spacing between rows with plants 18-36 inches apart within the row.

FERTILIZER

For the most current advice, see Nutrient Management for Sustainable Vegetable Cropping Systems in Western Oregon, available as a free download from the OSU Extension Catalog

A soil test is the most accurate guide to fertilizer requirements. The following recommendations are general guidelines:

The optimum pH range is 5.8-7.0.

Apply 10 tons/acre of manure in the spring when available.

Western Oregon – At time of seeding, band 2 inches to the side of the seed and 3 inches deep the following:

Eastern Oregon – At time of seeding, band the following:

Nitrogen: 40-60 (N) lb/acre
Phosphate: 115-125 (P2O5) lb/acre
Potash: 50-100 lb K2O/acre (broadcast and disked in prior to seeding).

Sidedress with 25-50 lb N/acre, or where mulching and trickle irrigation are practiced, N can be fed through the trickle irrigation system at 15-25 lb/acre when the vines begin to spread. To prevent clogging or plugging from occurring use soluble forms of nitrogen (urea or ammonium nitrate) and chlorinate the system once a month with a l0-50 ppm chlorine solution. Chlorinate more frequently if the flow rate decreases.

IRRIGATION

Summer squash roots to a depth of 3-4 feet. Maintain soil moisture above 60% of the soil water holding capacity. In western Oregon, 12-15 inches of irrigation may be necessary. Approximate summer irrigation needs for the Hermiston area have been found to be 3.5 inches in May, 5.0 in June, 7.5 in July, and 7.0 in August. It is important to regulate irrigation properly to avoid excessive moisture or water stress. Research has shown that the use of drip irrigation under black plastic mulch is superior to sprinkler irrigation with black plastic mulch. Yields usually increase dramatically.

See also the OSU Irrigation Guide for this crop.

FLOWERING AND POLLINATION

Zucchini and summer squash plants bear separate male and female flowers on the same plant (monoecious). Only the female flowers set fruit. Bees transfer pollen from male flowers to female flowers, making fruit set possible. It is recommended that one honey bee hive should be introduced for every 1 to 2 acres during the blooming period since native bee populations may not be adequate, or may not coincide properly with the blooming period.

Questions come up about cucumbers, melons, gourds, and summer and winter squash, crossing and affecting the eating quality of one vine crop or another. This is NOT a problem. Intercrossing is only a problem when seed is saved for replanting, in which case squashes of the SAME species need to be isolated for crop purity. Cucurbits of different species do not intercross sufficiently to create problems for seed producers.

GROUND MULCHES AND ROW COVERS

Black plastic ground mulch is sometimes used in the production of summer squash to enhance yield and earliness. It controls weeds, may increase soil temperature, conserves moisture, and protects fruit from ground rots. For black plastic mulch to increase soil temperature, it is imperative that the soil surface be smooth and that the plastic be in close contact with the soil. This can only be achieved by laying the plastic with a machine designed and properly adjusted for this task. Clear plastic mulch is very effective at transferring heat to the soil, but does not control weeds.

A new generation of plastic mulch films allows for good weed control together with soil warming that is intermediate between black plastic and clear film. These films are called IRT (infrared-transmitting) or wavelength-selective films. They are more expensive than black or clear films, but appear to be cost-effective where soil warming is important.

Plastic, spunbonded, and non-woven materials have been developed as crop covers for use as windbreaks, for frost protection, and to enhance yield and earliness. They complement the use of plastic mulch and drip irrigation in many crops.

Non-woven or spunbonded polyester and perforated polyethylene row covers may be used for 4 to 8 weeks immediately after transplanting or seeding especially for summer squash (such as zucchini) where the added cost could be recovered through increased early season prices. Covers should be removed when plants begin to flower to allow proper pollination. Row covers increase heat unit accumulation by 2 to 3 times over ambient. Two to four degrees of frost protection may also be obtained at night. Soil temperatures and root growth are also increased under row covers as are early yields, and in many cases total yields.

A new insect exclusion cover (Agryl P-10), is very light weight, offering season-long insect vector exclusion without affecting canopy temperature very much. It is recommended for trial in situations were conventional virus vector control procedures are inadequate, and market economics justify. It must be frequently manipulated; removed to allow bee pollination, and re-applied as necessary to exclude aphid virus vectors.

HARVESTING, HANDLING, AND STORAGE

The University of California-Davis has a file on Minimal Processing of Fresh Vegetables that discusses film wrapping and other topics.

In the Willamette Valley, summer squash and zucchini is harvested for processing from July 7 to September 20. The prime harvest period is from July 25 to August 25. Fresh-market plantings may be harvested up to two weeks earlier than this when transplanted on mulch and rowcovers are used. Fields are normally harvested every 2 to 3 days in warm weather. Cut fruit from the vine, leaving a piece of stem with the fruit.

Yields of zucchini for processing of approximately 20-25 tons/acre can be obtained form multiple harvests with zucchini planted at 24×36-inch spacing. Zucchini and summer squash can be harvested anytime fruits reach the desired size but before they forms hard seeds or rinds. For processing, zucchini is graded by diameter: Grade #1: 1″-2″; #2: 2″-2.25″; #3: 2.25″-2.50″; anything over 2.5″ is rejected.

Fresh market yields are approximately 150 to 300 cwt/acre depending on the number of pickings. When using appropriate plasticulture techniques, yields of 360 cwt/acre have been reported. Crook-neck, straight-neck and zucchini should be 1.25 to 2 inches in diameter and zucchini and straight-neck squash 7 to 8 inches long. Scallops should be 3 to 4 inches in diameter

STORAGE (Quoted or modified from USDA Ag. Handbook 66 and other sources)

Processing squash is not normally stored. For fresh market, store zucchini and summer squashes at 40 to 50 F and 95% relative humidity. Summer squashes, such as Yellow Crookneck, Yellow Straightneck, White Scallop, Zucchini, and other soft-skin types are harvested at the immature stage for best quality. They are quite perishable, as the skin is tender and easily wounded in handling. Small fruits are more desirable than large ones because they have a more tender flesh and a slightly sweet flavor.

Normally they should not be stored except long enough to accommodate normal marketing delays such as holidays and weekends. They can be held 1 or 2 days below 40 F with no discernible damage, but such exposure should be avoided as summer squash is chilling sensitive. Holding summer squash longer than 4 days at 32 F will cause chilling damage and more rapid deterioration.

The recommended temperature range is 41 to 50 F with 95% relative humidity. The storage life of summer squash is only 1 to 2 weeks. If storage of yellow squash extends beyond a week and distribution is involved after removal, storage at temperatures of 45 to 50 F is best. The storage period at 45 to 50 should be limited to 2 weeks or less. Recent research has shown that 41 F is best for Zucchini squash stored up to 2 weeks. Storage in low-oxygen atmospheres was of little or no value for Zucchini squash held at 41 F.

PACKAGING

Cucurbits, Leaf Spots

There are several diseases that cause leaf spots on these crops and they can often be hard to tell apart. Below are descriptions of some the more common fungal and bacterial leaf spots found on cucurbit crops in MA that we hope will help you tease them apart in the field. Of course a diagnosis from a trained pathologist in the lab is ideal, but we understand it is not always possible to test every spot you encounter.

Angular leaf spot (Psuedomonas syringae pv. lachrymans)

Angular leaf spot can affect all cucurbits, but cucumbers are most commonly affected. It is caused by the bacterium Pseudomonas syringae pv. lachrymans. This disease is usually among the first to show up because it is seed-borne. It will start to appear in the early to mid-season. Small, round water-soaked spots appear on leaf tissue, and expand until they are confined by veins, giving them the characteristic angular look. Under moist conditions a milky white exudate containing bacterial cells may ooze out of the lesion on the lower leaf surface. These wetlooking spots will dry out and turn yellow-brown or the dead tissue may fall out leaving a “shot-hole” appearance. Yellowing of the leaf between lesions may occur where disease severity is high. Similarly, water-soaked spots may appear on stems and petioles, drying out to form a whitish crust. Spots can also appear on fruit, where they are tiny and water-soaked but dry to form whitish, chalky, spots. These spots cause internal decay of fruit, and fruit that is infected early may be deformed. Affected plants will grow poorly, produce less fruit, and affected fruit is unmarketable.

As with other bacterial diseases, outbreaks of angular leaf spot are often initiated from infected seed. Bacteria proliferate in warm, moist weather and are spread from plant to plant by water, commonly in the form of splashing rain or runoff, as well as by insects or workers moving through the field.

Cultural controls:

  • Use resistant varieties.
  • Use drip irrigation to reduce spread of bacteria by overhead irrigation.
  • Don’t work in wet fields or work in clean sections of the field first and infected sections last to avoid spreading the disease to unaffected areas or to new plantings.
  • If you catch the disease early, before it is widespread and severe, copper may be effective in reducing its spread.
  • Till in residues quickly after harvest to get that infected tissue breaking down quickly. Bacteria survive on residues as long as it is present, up to two years.


Image 1. Angular leaf spot on zucchini, S. Scheufele

Anthracnose (Colletotrichum orbiculare​)

For more information on this disease, please see our main Cucurbits, Anthracnose article.

Anthracnose affects mostly melons, watermelons and cucumbers; squash and pumpkins are less susceptible. The disease is caused by the fungus Colletotrichum orbiculare which, like other anthracnose fungi, causes characteristic black, sunken lesions on affected fruit. Leaf spots are light brown or reddish and appear near veins so may cause leaf distortion. These lesions dry out and the dead issue may fall out, again leaving a “shot-hole” appearance. On stems and petioles, lesions are elongated and tan. The fruit lesions are large, circular, sunken areas that turn black and may produce a pink ooze under humid or moist conditions. The fungus can be seed-borne and also survives on crop residue or volunteer plants (maybe in your compost or cull pile?). Humid, rainy weather is necessary for disease to occur. There are three races of the fungus that affect different crops. Resistant cucumber and watermelon varieties are available, but there are no resistant melon varieties. There are many fungicides labeled for control of anthracnose; please see the New England Vegetable Management Guide for recommendations.

Image 2. Anthracnose lesions on watermelon fruit, OMAFRA


Image 3. Anthracnose leaf spot, R.L. Wick​

Alternaria Leaf Spot (Alternaria cucumerina)

For more information on this disease, please see our main Cucurbits, Alternaria Leaf Spot article.

Alternaria leaf spot affects all cucurbit crops but is most common on cantaloupe. The disease is caused by the fungus Alternaria cucumerina which, like other Alternaria species, can cause a characteristic target-like spot. Usually, leaf spots start out as small tan flecks that enlarge and merge together. These larger spots (up to a half inch) may exhibit the concentric rings common of Alternaria fungi. This disease usually occurs in mid-season and can reduce late-season fruit production. Fruit lesions may also occur–they appear as zonate, sunken lesions with dark, olive-green, felt-like sporulation present. The fungus survives on crop residue in the soil as long as it is present. A two year rotation away from cucurbit hosts is usually sufficient.


Image 4. Alternaria leaf spot on cantaloupe, G. Holmes

Septoria Leaf Spot (Septoria cucurbitacearum)

Septoria leaf spot is less common, occurring in cool summers or late fall. The disease is caused by the fungus Septoria cucurbitacearum which creates small, almost white round spots on leaves and superficial raised tan bumps on fruit. The fungus survives on crop residue in the soil which persists one to two years. Spores are spread from plant to plant via splashing rain or overhead irrigation.


Image 5. Septoria leaf spot on cucumber, R.L. Wick

Scab (Cladosporium cucumerinum)

For more information on this disease, please see our main Cucurbits, Scab article.

Scab, caused by the fungus Cladosporium cucumerinum, can be a significant problem for summer and winter squash, pumpkin, melon, and watermelon. Lesions may occur on leaves, stems, petioles, and fruit, with fruit spots being the most damaging. Leaf spots are small, pale-yellow to white, and again the dead tissue in the center of the lesion may fall out leaving a “shot-hole” appearance. Leaf lesions may not occur. Lesions on stems are elongate and light colored, and if numerous may cause the internodes to shorten, giving the plant a deformed virus-like appearance. Scab lesions on fruit are sunken, irregular cavities with corky margins, and may produce a golden brown ooze which dries into brown beads. Sporulation on lesions may occur, giving them an olive-green, felt-like appearance.

This disease usually occurs in mid-summer and is favored by cool dry days and rainy or dewy nights. The pathogen survives in crop residues which persist one to two years in soil. Tolerant varieties of cucumber are available. Chlorothalonil, mancozeb, or polyoxin D can be used preventively, at the first sign of disease.


Image 6. Scab on zucchini

–Susan B. Scheufele, 2015, updated 2016

Whether you’re a bonafide plant lady or a known succulent killer, you know that caring for your plant babies is not an easy feat. You can do all the right things—feed them water, put them near a window, incorporate them into your self-care routine, give them names and tell them how beautiful they are every morning (just me?)—and yet, sometimes your plant’s leaves start turning yellow.

To help solve our plant conundrum, we turned to a couple of green-thumbed pros to find out why (dear God, why?) those plant leaves are turning yellow (there are seven common reasons) and what you can do to keep your potted pals looking lush and oh so green.

Here are 7 reasons that could explain why your plant leaves are turning yellow

1. The plant needs more water

One of the things that can cause plant leaves to turn yellow is that the plant’s roots aren’t getting enough water. This can happen if you’re just watering the top of the soil. To fix this, Joyce Mast, Bloomscape’s “plant mom,” recommends soaking the bottom of the plant by filling up your sink with 2-4 inches of water and setting the plant in there for 30 minutes. This will allow it to soak up the water from the bottom. Next, drain the sink and let the plant rest there for a bit to let excess water trickle down. Repeat every four weeks.

2. The plant is overwatered

The color and tone of the yellow can also give you some clues as to what your plant needs. If the yellow leaves look dull and lifeless, Luz LeStrange, plant consultant at The Well, says that could mean your plant is getting too much water. Roots need air just like we do, Mast adds. And when we get a little water happy, the plant’s roots might not get enough air and start to drown and rot.

To remedy this, cut back on the H20 you feed your plant baby. LeStrange also suggests taking a sharp object (scissors, chopsticks, etc.) and probing the soil to let air in and let it breathe.

3. The plant is still getting acclimated

If you’ve ever moved houses, you know that it can often take a while for you to get all settled in and for the new place to finally feel like home. Plants are the same way. “If you have just purchased the plant, you may see a plethora of yellow on the leaves because it is still acclimating to its environment,” LeStrange says. “In this case, first ensure the plant has adequate light. Also, try spraying the plant with a mister and use a weak solution of micronutrient to help revive and relieve stress to the plant.”

4. The plant is sensitive to the water

Your tap water can also be to blame for the withering leaves. “Indoor foliage plants can have a sensitivity to the chemicals and minerals such as fluoride, salts, and chlorine often found in water from your faucet,” Mast says. “A simple remedy is to fill a pitcher or jug with water and let it sit uncovered overnight, allowing the minerals to evaporate. Another solution is to use distilled water or rainwater.”

5. The plant is getting too much light

While some greenery thrives when it’s in direct sunlight all day every day, plants that prefer low to medium light can get scorched when they get too much light. A quick Google search can help you learn what type of lighting works best for your particular plant. Otherwise, Mast suggests just moving the plant to different areas of your home where it’ll get medium to bright indirect light and see where it thrives best.

6. The plant is nutrient deficient

Just like us humans might need to pop a supplemental vitamin in order to get the nutrients we need, plants also need some extra nourishing sometimes that goes beyond light and water. “Most plants will benefit from fertilizing a couple of times a year in the spring and summer months,” Mast says. She recommends looking for a plant food with iron. “It is also a good idea to supplement with Epsom salts to provide adequate magnesium. A lack of magnesium often causes yellowing. When using fertilizers of any sort, always make sure the soil is damp before applying to the soil.”

7. The plant might have leaf spot disease

If your plant’s leaves have small brown spots trimmed in yellow, this could be a sign that it has leaf spot disease, which is a fungus or bacteria that feeds on the leaves. If this is the case, don’t start planning a plant funeral just yet. The problem is treatable. Mast’s advice is to immediately remove the affected leaves and isolate the plant from your other greenery for a bit.

“To treat leaf spot disease, put a tablespoon or two of baking soda and a teaspoon or two of mineral oil in a spray bottle of water,” Mast says. “Shake the solution well and then spray all areas of the plant that are infected with brown spots. It may take a couple of applications before the bacteria is totally gone.”

What to do to the yellow leaves

Now that you have a general idea of what might be causing your beloved fauna’s golden leaves, it’s important that you take care of the yellow leaves before you start to implement the new care tactics.

And by take care, we mean get rid of them. Their chances of turning green again are pretty much zero. “Remove the damaged area of a leaf or the complete leaf if it is entirely brown,” Mast says. “This allows the plant to direct its energy to new healthy growth.”

So reach for the pair of sharp scissors or pruning shears in your plant lady toolkit and get to cutting. Make sure to wipe the blades with rubbing alcohol between each snip. “For brown or yellow tips, remove just the brown or yellow part,” Mast says. “For fully brown leaves, cut near the base. You may need to do this in stages because you never want to remove more than 30 percent of the affected leaves at one time.”

Looking to add to your leafy brood? Here’s how to choose the best plant for you personality. And this is how to use feng shui for plants arrange them for optimal good vibes.

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Even the most novice of gardeners knows that indoor plant leaves turning yellow is not a good sign. The problem is that yellow leaves is the most common symptom of a wide range of houseplant ailments, and it can take a little experience to know what the root of the problem is. Sometimes it can be serious, sometimes it’s temporary and sometimes you may have to change up your care routines to fix it.

Here are the common reasons why your plants leaves may be turning yellow, and some easy steps to get them healthy again.

1 – Lack of Sunlight

Getting too little light is one possible cause for yellowing leaves, and the first thing most indoor gardeners think of. While a likely source of concern, it’s just one of many. Are the leaves closest to the light still green, and only yellowing on the far side? That can be your hint that light is the cause.

Find a sunnier location, or make an effort to turn the plant more often so that the backside is getting enough light. Adding an artificial light source can also solve the problem. It doesn’t need to be a fancy plant light either.

A standard lamp can be enough to green things back up again. If you can, choose a bulb that is “cool” in color tone rather than “warm” (in other words, slightly blue instead of slightly red) to encourage greener leaves.

Sometimes having too much light can also cause yellowing but that usually changes to brown as the leaves dry out. Unless you have a very hot or sunny location, or are growing shade-loving plants, this is a lot less likely than having too little light.

2 – Low in Nutrients

Plants will also start to yellow when they are not getting the right balance of nutrients. It may be a number of elements, but it’s probably a nitrogen shortage.

Nitrogen is necessary for lush green leaves and will be depleted if you haven’t repotted your plants for a while. Is it the newer leaves that are yellow? That’s nitrogen.

On the other hand, are leaves turning yellow in different patterns (yellow along the veins, or just the edges?), then there is another problem with the soil. Yellowing on the edges is probably a lack of potassium, for example.

A little soil test kit (view on Amazon) can let you know what your soil is lacking. Once you pick one up, simply follow the directions. It usually just means taking a sample of your potting mix, adding water and the various reagents in the kit. Compare the color to the chart, and that’s it.

Fixing a nutrient problem is as simple as getting a little fertilizer, as long as you have narrowed down what minerals you are lacking. Fertilizers come in a huge range of nutrient contents and concentrations. Adding the wrong one can make things worse, which is why you need to do the tests first.

Though not exactly the same as nutrient content, having soil with the wrong pH level can also lead to unhealthy plants and leaves turning yellow. The pH should be roughly neutral (or 7), and it can get too acidic over time, and organic compounds in your potting mix start to break down. You can get a separate testing kit for this. Just remember that the lower the number, the more acid the soil.

3 – Watering Problems

This can be either too much (see my fixes for overwatering) or too little watering. For plants that are not getting enough water, you’ll actually see wilting as the first symptom. Without the water pressure inside the plant, it droops. After that, there can be yellowing before they lose the leaves entirely.

Check on the water needs of your plants, and then double-check you are not giving too much or too little. Does the soil stay wet or soggy for too long after you water the plants? A lack of drainage could start to water-log the roots even if you are actually watering them correctly.

It might seem like a positive thing that the soil holds on to water so you aren’t getting out the watering can every day, but its not a great situation for plants because their roots do need to breathe.

If drainage is the case, you will want to consider repotting the plant in looser soil or potting mix that provides better drainage. Materials like peat moss, shredded coconut fiber, sand or perlite are all good options.

4 – Environmental Shock

Plants generally do best in a relatively constant or at least seasonal environment. Some types of changes can shock them, leading to yellowing and dropping of leaves. As long as the change isn’t a hazard to the plant, it will certainly recover with a little added care.

One possible shock is that you’ve recently repotted your plant. It’s not that you necessarily did it any harm, it’s just that the sudden change in soil chemistry and even just having more space for the roots can trigger a surprise for the plant. It should be fine with a little time.

Another possible shock is a drop in temperature. Not all plants are super sensitive to temperature changes, but there are some indoor plants that are not happy to get chilled.

Check your plant area and see is something has changed. Too close to an air conditioning vent, a newly opened window or anything else that would bring the temperature down from where it used to be. Now in this case, you want to find the source of the draft and fix it, rather than hope the plant adjusts (it probably won’t).

5 – Insect Pests

By now, you have probably solved your problem of leaves turning yellow on your houseplants. If not, there is still another possible cause: insects.

You might think that if you had bugs in your plants, you would notice but they can be masters of staying hidden under the leaves, especially if you have a large indoor garden area that is packed with plants.

Insects that suck sap out of your plant are the problem. Aphids are one example that many indoor gardeners have had to deal with. They are small and translucent, and have a sneaky habit of clustering on the undersides of the leaves where you don’t realize they are there.

Though tiny, when you have enough of them, they can start to seriously drain the fluid from your plants. This creates the same situation of having too little water, as we mentioned earlier.

Use a spray of insecticidal soap on any aphids you see, and it should clear up the problem quickly. You will have to give your plants a close exam to make sure you get them all though.

For more tips to rid your plants of bugs, see my detailed article on controlling indoor plant pests.

6 – Broken Stem

When a stem gets bent suddenly, it may crack somewhat inside without showing a break on the outside. Water stops flowing to the rest of the stem, and you get yellow leaves and wilting. But only where the damage is, so it kind of stands out that only one single section is suffering. You can just snip it off with clean scissors and your plant should be fine.

7 – Nothing is Wrong

Individual leaves on a plant do not live forever, and will often turn yellow as they die off naturally. They’ll tend to be the older leaves, and the rest of the plant will be doing fine.

Are you growing plants that may have variegated leaves? Sometimes new leaves start out green and slowly develop a mottled yellow/green pattern as they mature. If you’re not expecting it, it can make it look like your plant is unhealthy.

Your yellowing leaves may not be less of a mystery yet, though now you have a few different things to look at more closely to get things greening back up again. With all these possible issues, you should be able to easily diagnose your problem.

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163shares Indoor Plant Leaves Turning Yellow (Fixes for 7 Common Causes) was last modified: July 8th, 2019 by The Practical Planter

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