Warm-Season Plant Problems and Solutions

Sungold tomato planted 6 weeks ago is developing nicely with all the cool weather we've had and additional watering besides our couple of rains. Now that the plant is multi-branched and above the cage's second rung (about 1 foot tall), I'm letting it set its blossoms for my first fruits of this season. I wait until the plant is this tall and well-developed before letting the blossoms set because I want the plant to put all its energy into establishing an extensive root system before redirecting that energy into ripening fruit.

My nasturtium "ocean" with the -everblooming salvia on the right.

Nasturtium up close.

The everblooming salvia up close.

The first artichoke fruit on a plant is always the largest. Succeeding ones are progressively smaller, until the "baby" sized ones at the end of the season. This gradually smaller sizing has nothing to do with your fertilizing or watering patterns.

Stock's new blooms and old expended seed pods.

Bladderpod.

Several roses blooming after last October's pruning.

Several brassicas going to seed.  Fortunately, the foliage - including the blossoms themselves - is still tender and sweet, great raw for salads and stir-fried or cooked. 

Thickly-sown seeds that seemingly all germinated make for easy trimming for salads or stir-fries, even as they send up their tiny seedstalks due to warm weather.

Tiny hummingbird mother facing to the right in her brown nest in the center of the picture just to the left of the brown oak leaf.

Two even tinier hummingbird babies with beaks pointing up. Happy Easter Birthday!

Four variations of Ferraria crispa.  Although each bloom lasts only one day, each stem has a couple of dozen that open gradually.  The whole display may last a month.

Brown blossom of Salvia lutea. This photo show it a bit pinker than it really is.

Several freesia colors.

Sea lavender, Statice - Limonium perezii - thrives without any other water than rain - even our minimal amount!

Encelia.

Beets harvested when the globes are 1.5 inches. I left all the ratty old leaves in the compost pile and cut off the root. In my kitchen, I'll cut off the remaining young leaves for salads or stir-fries, and cook the beets, and then pickle them.

The first beans coming up! If you've never grown them from seed before, be aware that they appear to come up "backwards" when they burst through the soil. Let them be, as they'll continue to unfurl and grow "straight up".

Scilla peruviana, Portuguese squill. 

Iris nana. Perfect for light shade next to begonias.

Four camellias blooming.

Acanthus 'Whitewater'

New mulberry fruits forming.

Tendergreen peas blossoming and bearing fruit. I immediately munch at least as many as I finally end up bringing down to the kitchen.

     With this week’s daytime temperatures topping 90 degrees every day, and nighttime temperatures above 60, it appears that we’re finally moving into summertime.  My first beans, cukes, and squash have germinated, and my tomatoes are well up to the second rung on their cages and putting out blossoms.  So I thought I’d provide these warm-season-plant-problems-and-solutions tips earlier in the season so you can be ahead of the curve in checking out your plants and taking care of any issues. 

Previous Blogs you may want to refer to, about everyone's favorite veggie - TOMATOES - are:
6/17/20 Tomato Growing Problems and Solutions
3/20/20 Happy Spring!  Transplanting Tomatoes Technique 
 
Beans
PROBLEM:   Healthy  plants that drop their blossoms or stop setting  them  may be strained from a previously heavy harvest,  or some overmature pods may still remain on the plant, thus inhibiting the setting of new fruit.  Too much nitrogen fertilizer can also contribute, as can hot weather over 85 degrees and low soil moisture.  After air temperatures return to below 85 degrees, it may take another two weeks for plants to set new blossoms.
SOLUTION:  Make sure to harvest all pods as they mature, and wait for new pods to set.   Incorporate a balanced fertilizer, and sidedress with a low-nitrogen fertilizer.   Plant  early in the season to avoid hot weather during the blossoming period, and water deeply and more frequently.
 
PROBLEM:  Bacterial blight  spreads quickly on wet foliage and is evidenced by large brown spots on leaves and water-soaked spots on pods.
SOLUTION:  Pull up and destroy (don’t compost) affected plants.  Avoid handling wet foliage.
 
PROBLEM:   Leaves with small red or black blisters that turn yellow,  dry  up, and drop are affected by rust.
SOLUTION:  Plant resistant varieties.   Destroy diseased plants after harvest.  Use new stakes for climbing varieties.  Avoid handling foliage when the plants are wet.
 
PROBLEM:  Beans become shriveled and limp when they have received insufficient irrigation.
SOLUTION:  Beans should never dry out.  Never handle the plants, however, when the foliage is wet.                 
 
Corn
PROBLEM:  If plants grow slowly early in the season,  the climate is still too cool.
SOLUTION:   Cover  plants  with hotcaps to retain heat, or  wait  for  warmer weather to sow the seed.
 
PROBLEM:   Leaves  that roll upwards indicate that the plant  needs  immediate irrigation.
SOLUTION:   Irrigate more deeply and frequently to keep soil consistently moist.   Provide organic mulches  to retain soil moisture.
 
PROBLEM:   Leaves  that  develop green and yellow striping at their  base  are deficient  in  zinc.   This occurs more frequently on wet heavy soils  in  the early spring and may be due to excessive phosphorous.
SOLUTION:  Incorporate manure.
 
PROBLEM:  Leaves that appear streaked are deficient in potash,  especially  if the plants are grown on very light soil that is easily leached.
SOLUTION:  Incorporate manure,  seaweed,  wood ashes, greensand, granite dust, non-woody plant residues, manure, or compost to aerate the soil.
 
PROBLEM:  Yellow striping on leaves indicate a manganese deficiency, especially on soils with a pH above 6.7. 
SOLUTION:  Incorporate manure that includes micronutrients.
 
PROBLEM:  Reddish streaks on leaves point to a phosphorus deficiency.
SOLUTION:  Sidedress with a complete fertilizer.
 
PROBLEM:  Holes can be chewed in leaves by various insects.
SOLUTION:  Ignore the damage unless it is severe,  or handpick and destroy the insects.  The loss of a small amount of leaf will not reduce the yield.
 
PROBLEM:  Stunted plants with speckled leaves and ears that are filled but may have missing kernels have sugar cane mosaic.
SOLUTION:  Plant resistant varieties.
 
PROBLEM:   Stalks that fall over after a moderate wind,  especially after rain or irrigation,  need to have their roots anchored better. 
SOLUTION:   Corn is naturally shallow-rooted and needs to have soil hilled  up around  the base of the stalks.   Add more every two weeks until tasseling  begins.   This extra soil also serves as a mulch to retain moisture.
 
PROBLEM:   Corn earworms are bright green to purplish-brown worms that may  be present  on the silks or eating their way down through the kernels at the  tip of the ears.   Brown,  sawdust-like material close to the damaged area  accompanies the worm.
SOLUTION:   Plant  resistant varieties as early in the season as  possible  to avoid higher populations later in the summer.   Apply Bt, lime, or mineral oil to  silks  just inside the tip of each ear as soon as the silks have begun  to turn brown.  Applying these sooner will interfere with pollination and  result in poorly-filled ears.   In hot,  dry weather,  however, the oil may spoil the ears.   Encourage lacewings,  toads, spiders, and ladybird beetles.  Break off and  destroy  the damaged portions of the ears.   Destroy (don’t compost) the ears or portions which  have been damaged to prevent the worm from maturing.
 
PROBLEM:   Small  ears that are poorly filled with incompletely  developed  or shriveled kernels - but with no insect damage - result from poor  pollination, insufficient irrigation (especially from silking through harvest), hot weather or  high winds from two to three weeks before harvest,  or planting a  variety that is not adapted to the area.
SOLUTION:  Plant corn at least four rows wide and long to encourage pollination by breeze.   Water and fertilize the corn well,  as it is a heavy drinker and feeder. Grow varieties that are appropriate to your area.
 
PROBLEM:   Kernels that are tough and doughy, somewhat shrunken, and taste starchy haven’t been watered enough. 
SOLUTION:   Irrigate corn deeply for the approximately three weeks  from  when the  silks  first appear until they dry up and the kernels are full  of  milky juice.   If the corn is not harvested during this milk stage,  its sugar turns into starch.
 
PROBLEM:   Large gnarled galls that are greyish-white to black are from a smut infestation  that thrives in hot,  dry weather.   Late-maturing corn  is  more susceptible.
SOLUTION:   Plant fungus-disease-resistant seeds early in the season on a  three-year rotation  of  crops.   Remove and destroy affected plants as soon as they  are noticed, and keep the powder from spreading.  Do not compost. Huitlacoche is prized in the Hispanic and Latino culture.
 
Cucumber Family:  Cucumber, Pumpkin, Squash
PROBLEM:  When vines wilt, and leaves have small specks which turn yellow, and brown, the squash bug has infected the plant.
SOLUTION:   Handpick  and destroy the adults and their  egg  clusters.   Plant resistant varieties.   Rotate crops.   Apply wood ashes or an ash-water spray.  Squash bugs hate catnip,  pink petunias,  radishes,  marigolds, orange nasturtiums, and tansy, so planting these will provide garden beauty while deterring the  bugs.   Plant  new  crops as far away as possible  from  the  previously-infested crop.  Trellised plants are less susceptible. 
 
PROBLEM:  Leaves that are eaten may have been enjoyed by the cucumber beetle.
SOLUTION:  Plant late in the season.  Cultivate the soil thoroughly, and mulch heavily.  Dust plants with rotenone for a serious infestation.  Striped cucumber beetles love goldenrod more than cucumbers, melons, and pumpkins, so plant some of these as sacrificial attractants.   Interplant with catnip, radish, or tansy.  Natural enemies are the soldier beetle, braconid wasp, and nematode.
 
PROBLEM:  If plants suddenly wilt,  have parts chewed, and yellow sawdust-like deposits are at the base of the stems, the squash vine borer is in residence.
SOLUTION:  Make succession plantings. Slit the stems and remove and destroy the borer.   Cover the damaged area and every fifth leaf node with soil to encourage rooting,  so that the vine will continue to grow beyond the slit.  Destroy (don’t compost) all vines after harvest.
 
PROBLEM:  When mature plants are healthy but no blossoms or fruit set after  a particularly  heavy  harvest or some mature fruits still remain on the  plant, the plants are just temporarily resting from their exertion.
SOLUTION:  Harvest as fruits ripen, even if they will not be used immediately.
 
PROBLEM:  Blossoms that appear but don't set fruit,  or the fruits shrivel and fall off,  may result from several causes.  Early-season flowers are male, and female  blossoms will follow and set properly.   Blooming and fruit  set  will resume about a week after night temperatures that were too cool or too hot, or an unusually heavy fruit set.  In addition, lack of moisture, poor soil fertility, too much shade, and various diseases may also contribute. 
SOLUTION:   Fruit  should  set properly later in the  season.   Irrigate  more frequently and deeply to keep soil evenly moist.  Incorporate a complete fertilizer.
 
PROBLEM:  Cucumbers that taste bitter, especially just under the skin and more deeply  at  the stem end,  may be due to older  varieties,  overmature  fruit, alternately hot and dry temperatures,  daily temperature fluctuations that are greater  than 20 degrees,  excessive nitrogen,  or irregular growth  resulting from inadequate or infrequent moisture.
SOLUTION:  Choose newer varieties.  Irrigate more deeply and frequently during hot,  dry weather,  and harvest fruit when it is ready.  For eating,  cut  and discard the bitter end portions,  and heat the cucumbers for one minute in boiling water to draw off the bitterness, then discard the water.
 
PROBLEM:  Misshapen fruits can result from inadequate moisture,  poor pollination,  or confined development.  When the weather is too cool or too hot, bees are  not available,  and pollination is not complete.   When blossoms cling to the  fruit after overhead watering,  or the fruit is confined in the  foliage, fruit development is restricted, and odd shapes result. 
SOLUTION:   Irrigate  more  deeply and  frequently,  and  underneath  foliage. Encourage  bees  to your garden by  providing  blue-flowering  plants.   Avoid overhead  watering during blossoming.   Provide trellises or other support  to release fruits from being bound in the plant foliage.
 
PROBLEM:  Scab,  which thrives in foggy, cool weather, causes dry, corky spots on fruit,  leaves,  and stems.   Sap oozes from the fruits,  and greenish mold develops.
SOLUTION:   Pull up and destroy (don’t compost) infected plants immediately.   Plant resistant varieties.   Rotate the crop so that they are not grown in the same soil  more frequently than every three years.
 
PROBLEM:   Squash and pumpkins that rot during storage were probably not  sufficiently cured or properly stored - or are next to ones that are spoiling.
SOLUTION:   Let the fruit mature completely before harvesting,  and cure  them thoroughly.  Store in a dry place out of direct sun at 40 to 60 degrees.
 
Melons:  Cantaloupe, Honeydew, Muskmelon, Watermelon
PROBLEM:   When vines wilt and leaves have small specks which turn yellow  and brown, the squash bug has infected the plant.
SOLUTION:  Handpick the adults and their egg clusters.  Plant resistant varieties.   Rotate crops.   Apply wood ashes or an ash-water spray.   Squash  bugs hate pink petunias,  radishes,  orange nasturtiums, and marigolds, so planting them will provide garden beauty while deterring the bugs. 
 
PROBLEM:  Melons taste bitter when they ripen in cold, wet weather. 
SOLUTION:  Plant melons so that they mature in warm weather.
 
Peppers and Eggplants
PROBLEM:  Leaves roll downwards, but there is no yellowing or stunting. 
SOLUTION:  Nothing is needed, as the fruit yield will not be affected.
 
PROBLEM:   Plants  that  grow very slowly and either don't set blooms  or  the blooms  drop off are suffering from weather that is too cool.
SOLUTION:   Wait until warmer weather to plant,  or provide hotcaps to concentrate the warmth.
 
PROBLEM:  When mature plants are lush, but no fruit sets, too much nitrogen is the problem.
SOLUTION:   Incorporate  a balanced fertilizer  when  planting,  and  sidedress several times during the growing season with a low-nitrogen fertilizer.
 
PROBLEM:   Pepper blossoms or young fruit drop when plants have been  stressed from  lack  of water,  air temperatures above 85 degrees,  too many mature fruits not  yet harvested, or magnesium deficiency.
SOLUTION:   Peppers  are only moderately deep-rooted and recover  slowly  from drought injury.   Harvest fruits,  and blossoms will begin setting  again.   A solution  of one tablespoon of Epsom salts to one quart of water sprayed  onto leaves  and  blossoms several times through the bearing season will aid  fruit set.
 
PROBLEM:  Peppers may be eaten from the inside by pepper maggots.
SOLUTION:  Destroy (don’t compost) the affected fruit.   Spray adult flies (yellow with  brown bands on wings) with rotenone before they lay maggot eggy in the peppers.
 
PROBLEM:  Eggplant fruit have brownish spots of rot that are especially severe during wet weather.
SOLUTION:   Plant  resistant varieties.  Rotate so that they are not grown  on same soil more frequently than once in every 4 years.
 
Potatoes, Sweet
PROBLEM:   Stem rot causes young plants to die after transplanting,  and  survivors develop bright yellow leaves which pucker,  wilt,  and die.  Harvest is of poor quality. 
SOLUTION:   Plant certified seed of resistant pieces.   Rotate the crop  so that plants grow in the same soil only once in four years.  Avoid overcrowding and overfertilization.
 
PROBLEM:  Tubers that are long and thin have received too much nitrogen.
SOLUTION:  Incorporate a balanced fertilizer when planting, and sidedress with a low-nitrogen fertilizer.
 
PROBLEM:  Tubers with a brown to black surface discoloration that is only skin deep and can be scraped off easily have scurf.  It is most severe on heavy wet soils with a high level of manure.
SOLUTION:   Plant healthy sprouts from certified seed stock.  Incorporate compost to lighten the soil and provide better drainage.  Rotate the crop so that potatoes grow in the same soil only once every four years.   Eating quality is not harmed.
 
PROBLEM:   White mold starts on bruised areas and develops into  soft,  watery rot on stored tubers. 
SOLUTION:   Plant certified seed of resistant varieties.   Avoid  bruising tubers  during harvest.   Cure tubers in a dark,  humid,  and  well-ventilated atmosphere at 80 to 90 degrees for two weeks.  Store in a dry, well-ventilated area at 55 to 60 degrees.  Avoid overcrowding.
 
PROBLEM:   Tubers are rough and oddly shaped when they are grown in soil  that is too heavy.
SOLUTION:  Incorporate organic matter to lighten the soil texture.
 
PROBLEM:  Tubers are dry and rough-textured when they have endured alternately wet and dry conditions.
SOLUTION:  Irrigate deeper and more frequently.
 
Potatoes, White
PROBLEM:  Potatoes that fail to emerge after planting the seed pieces in  cold wet  soil  may  have rotted.   If the potatoes were purchased at  the  grocery store, they may have been sprayed with a sprout retardant.
SOLUTION:  Plant only certified seed of resistant pieces when the soil has warmed.  Incorporate compost to lighten the soil and provide better drainage. 
 
PROBLEM:  Potato tuberworm eats tunnels in the tubers, and the shoots wilt and die. 
SOLUTION:   Keep potato plants deeply hilled with soil.  Don't allow  soil  to crack.  Destroy infested vines and tubers.
 
PROBLEM:   Leafroll  virus  and net necrosis cause plants to  be  stunted  and markedly  yellow  and leaves to uniformly roll upward.  Cut tubers have  brown netting.
SOLUTION:  Plant only certified seed of resistant pieces.   Spray peach trees for  overwintering green peach aphid (the carrier).
 
PROBLEM:   Stunted  growth and leaves that turn yellow and brown  between  the veins and become brittle may be suffering from magnesium deficiency.
SOLUTION:  Incorporate dolomitic limestone or a handful of Epsom salts.
 
PROBLEM:  Rhizoctonia,  black scurf,  causes vines to suddenly wilt,  stems to have brown lesions,  and tubers to have irregular raised,  black,  hard bodies and  be  roughened in a cross-patched pattern.   It is more prevalent in  wet, cold, heavy, and poorly-drained soil.
SOLUTION:  Plant clean certified seed of resistant varieties.  Rotate the crop to  a  new area with cereal or corn crops on a five-year  basis.   Incorporate compost  to lighten the soil and provide better drainage.   Plant as  late  as possible in the season.
 
PROBLEM:   Tubers  crack  from sudden growth resulting from  heavy  irrigation after long drought conditions.
SOLUTION:  Water deeply and more frequently in dry weather.
 
PROBLEM:  Tubers are knobby-shaped or have cavities in their centers when they have undergone alternately wet and dry conditions.
SOLUTION:  Irrigate to keep soil more evenly moist.   Incorporate compost to lighten the soil and maintain a more even moisture.
 
PROBLEM:   Tubers  with corky scabs on their skin surfaces are  infected  with common  scab  that is most frequently a problem in  dry,  sandy,  or  gravelly  soils that are alkaline,  lacking in organic matter,  or have a high level  of fresh manure.
SOLUTION:  Plant resistant varieties.  Avoid using wood ashes,  lime, or fresh manure.   Potatoes are safe to eat after removing the scabby areas.  Incorporate  compost  to improve the soil texture and its ability to remain moist  but not wet.   Grow and turn under a green manure crop - the soil will become more acidic,  and rapidly decaying matter will encourage beneficial organisms  that compete with scab.  Rotate crops on 5-year basis.
 
PROBLEM:   Stored  tubers  become soft and rotten from infection  that  gained entrance through wounds inflicted during harvest and storage.
SOLUTION:  Avoid wounding tubers during harvest and storage.

Tomatoes
See my previous Blogs:
6/17/20 Tomato Growing Problems and Solutions
3/20/20 Happy Spring!  Transplanting Tomatoes Technique 



More Gardening Tips for This Month
See March and April.
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