n00bgardener
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Cucurbit Diseases - ID and Advice

I seem to have a major problem with my cucumbers and bitter gourds (and other plants) So I am looking forward for some advice from you wise people.

Bitter Gourds
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Cucumber
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Okra
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Question: Whats wrong with the Drumstick(moringa) plant in the background? Why is it yellow ? I accidentally put in 5 grams of 19:19:19 NPK crystals on the root a few days back. Could that be the issue ?

Brinjal
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What could be wrong?

Cauliflower:
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What are those white patches ?


Lemons:
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Are they all ok ? Whats with the curled up leaf ?


Thanks in advance!

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applestar
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Cucurbita are prone to fungal diseases and these look like some advanced cases.
Make sure they have good ir circulation -- since they are in pots, move them away from structure and each other. Cut off and dispose of badly affected leaves so they don't spread, and spray clean and slightly affected leaves with one of the following organic fungicides -- hydrogen peroxide, baking soda (bicarbonate of soda) solution, or neem oil solution; alternate with milk solution to encourage beneficial bacterial colonization. (post which ones you want to use and we can discuss ingredients and details).

Looking at the brinjal (aubergine/eggplant) pot, the soil medium appears to be straight garden soil. This would be dense and slow draining. Any plants in containers need well draining medium -- 25-30% coarse sand/small gravel/shredded bark or root or nutshell mulch -- should be bended in.

The cucurbita and brinjal need very large containers -- these don't look big enough, so this might be a good chance to uppot in better soil mix with aged manure/straw in the bottom for extra feed.

Spots on the cauliflower could be sucking insects on the other side, but be aware that cauliflower is a cool season crop plant and by the time cucurbita and brinjal are growing well, it is usually too hot.

The lemons look great -- I wish mine would do as well. 8)

imafan26
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I see leaf miners and the moringa and eggplant look like they were over watered. Dirt is not a good choice in pots because it does not have enough air space for roots to breathe. Pots especially plastic and glazed ceramic cannot breathe and usually do not have enough drain holes. When dirt in pots are watered they expand and take up what little air space there is, water puddles on top and drains poorly. Roots need air to breathe. Back off on the watering and if the roots are not dead they may recover. If they do, then transplant to a pot with potting soil and use pots with lots of drain holes on the bottom and the sides.

There looks to be some fungal diseases as Apple said.

The holes in the leaves can be from slugs, or beetles.

I found a good link below that might help with identifying the problems.

https://www2.ca.uky.edu/agc/pubs/id/id91/id91.pdf

n00bgardener
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applestar wrote:Cucurbita are prone to fungal diseases and these look like some advanced cases.
Make sure they have good ir circulation -- since they are in pots, move them away from structure and each other. Cut off and dispose of badly affected leaves so they don't spread, and spray clean and slightly affected leaves with one of the following organic fungicides -- hydrogen peroxide, baking soda (bicarbonate of soda) solution, or neem oil solution; alternate with milk solution to encourage beneficial bacterial colonization. (post which ones you want to use and we can discuss ingredients and details).
This is some close cultivation I am doing, so air circulation is limited… Also I am co-hosting 2 plants of Bitter Gourd and 4 cucumbers (pot to pot + 3 inches). I got a yield of 9 full size cucumbers already. I spray 1:9 milk/water every 25 days (am I doing ok?). But was not using any fungicide/insecticide. Of-late I am using a 90% neem oil and a 0.03 (300 ppm) Azadirachtin spray at 3 ml per liter (0.26 gallon) water. But yet the bitter gourds have holes on it.. I caught a caterpillar redhanded biting into a bitter gourd. I sprayed some neem at 3ml/liter - lets see what happens in the morning.

Unfortunately, its now 98% of the plant… will chop the plant off..

I'll post up broader pictures of my terrace tomorrow (when there is light)
applestar wrote:Looking at the brinjal (aubergine/eggplant) pot, the soil medium appears to be straight garden soil. This would be dense and slow draining. Any plants in containers need well draining medium -- 25-30% coarse sand/small gravel/shredded bark or root or nutshell mulch -- should be bended in.
So the way I made my soil was 33% compost, 33% soil, rest coconut fibre shreds. I also put in DiAmmonium Phosphate. Is that wrong? I topped up using normal soul because I thought the roots were exposed!! Stupid me!
applestar wrote:The cucurbita and brinjal need very large containers -- these don't look big enough, so this might be a good chance to uppot in better soil mix with aged manure/straw in the bottom for extra feed.
The cucumber is in 12" pots, Brinjals are in 18", 14" and 12" - I wanted to measure the growth.. Will share that too tomorrow.
applestar wrote:Spots on the cauliflower could be sucking insects on the other side, but be aware that cauliflower is a cool season crop plant and by the time cucurbita and brinjal are growing well, it is usually too hot.
Will put in a close up snap too.. could the neem mix I use fix it ?
applestar wrote:The lemons look great -- I wish mine would do as well. 8)
Perhaps its the climate here.. The flowers got pollinated last month.. It seems to have some leaf curls.. Will try a closeup tomorrow.. Its being grown in an 18" pot.. with great drainage and water retention using coco-peat.. am I doing it well ?

n00bgardener
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Lovely note on the moringa... its planted in my leaf mold.. Basically I took all dry leaves and put them in a plastic bag with holes to push out water.. watered contents once a month for 7 months till it became mold
Will neem solve leaf miners if applied on early stages ?
Your suggestions were very helpful! I'll apply them!


imafan26 wrote:I see leaf miners and the moringa and eggplant look like they were over watered. Dirt is not a good choice in pots because it does not have enough air space for roots to breathe. Pots especially plastic and glazed ceramic cannot breathe and usually do not have enough drain holes. When dirt in pots are watered they expand and take up what little air space there is, water puddles on top and drains poorly. Roots need air to breathe. Back off on the watering and if the roots are not dead they may recover. If they do, then transplant to a pot with potting soil and use pots with lots of drain holes on the bottom and the sides.

There looks to be some fungal diseases as Apple said.

The holes in the leaves can be from slugs, or beetles.

I found a good link below that might help with identifying the problems.

https://www2.ca.uky.edu/agc/pubs/id/id91/id91.pdf

n00bgardener
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Please find attached broader pictures of the setup

thanks!

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applestar
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I love it! Your rooftop garden looks really great :D

I do think you underestimated the size of pots. The okras too. The tomato pots look more like the sizes they need at minimum. Bigger, really, would be better -- like half barrels, or a large water trough (with drainage holes) along the wall (ingenious trellising, btw).

Those squiggly white lines are leafminers for sure. (good eyes imafan!) I just read somewhere --didn't keep the link-- that Spinosad works on citrus leaf miners if applied in early stages of infestation. You can also simply squish them inside the leaf -- look for bulge or dark shadow at end of squiggle -- or cut or punch the entire squiggle out and dispose properly.

Of the cucurbita, gourds are least susceptible to mildew and most drought tolerant -- and that seems to be the case here. I suspect that with restricted root system and drying out, these plants are stressed out and more vulnerable to disease. Stressed plants are attractive to pest insects.

Remove leaves that have no green in them -- they are of no use now and only vector for pests and disease -- Up the concentration of milk to 30-40% and apply alternate weeks with the fungicide.

I would harvest the cucumber and call the plants done, and start a new batch of seeds/plants. If there is some kind of limitation to the growing season, plant a faster maturing variety. Also, southern gardeners find cucumbers do better in partial shade. Even here, I can grow them in part shade though probably not as productively. Could yours be getting too much sun? (Again, gourds and melons would do better than cukes in heat and sun.)

If you have sufficiently long season ahead of you, you may want to try Armenian or Persian cucumbers which are related to melons.

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applestar
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So the way I made my soil was 33% compost, 33% soil, rest coconut fibre shreds. I also put in DiAmmonium Phosphate. Is that wrong? I topped up using normal soul because I thought the roots were exposed!! Stupid me!
If that's what you have in the pots, it sounds pretty good but I would have added sand or gravel or something (Pumice gravel, perlite, composted bark chips) to increase drainage.... Unless the compost had unscreened larger bits like half decomposed nut and eggshells, sticks, fruit pits, seashells, crab/lobster shells.... Those bits and pieces are in my compost.)

I don't know what diammonium phosphate is so I can't comment. I tend to add dolomitic lime, rock phosphate, and green sand.

As for "topping" with soil -- what happens when you water? If the water sits on top of the soil, then it's not draining well. I would have mulched exposed roots with compost and coco fibre shreds.

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rainbowgardener
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You've gotten really good advice already and I don't have much to add. But it looks like the soil in your pots probably settled. They could all use to be "topped off." Not only does that give the plants more soil to draw from, but especially for young ones like the eggplant, it keeps them from sitting down in the shade and air circulation barrier of the pot.

But top off with whatever potting mix you were using in the rest of the pot. If your soil is clayish, as it looks, spreading a layer of that on top of your potting mix just acts like a seal.

Personally, I wouldn't put any garden soil in smallish pots like that, just fine-textured compost, the coco-fiber, and some of the kinds of things applestar was suggesting for keeping air and water channels, which could also be perlite, rice hulls, crushed lava rock, etc.

Nothing much that you spray on the leaves will take care of leaf miner larvae, which are protected inside the layers of the leaves. Just pull the leaves or the part of it with the critter in it as applestar suggested and dispose of it.

For future reference if you can find lambsquarters, columbine, or velvetleaf, they are good trap crops for the leaf miners. Lambsquarters is a common weed [where I am]. Velvetleaf is a wildflower. Mine came from a packet of mixed wildflower seed. Columbine is a very pretty shade plant. I have velvetleaf that pops up around my property ever since I planted the wildflower seed (everything else died out). The leaf miners love the soft leaves of the velvet leaf and leave everything else alone. I just have to keep pulling the squiggled leaves off the velvetleaf.

I don't know if any of those grow where you are, so you might have to ask around if there are local plants that work as trap crops for them..

n00bgardener
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Really cool advice @rainbowgardener and @applestar. Following up on your advice I am gonna trash the vines and start all over again. This time I will be careful, the biggest mistake I made was applying no neem sprays untill the disease was rampant.. This time I will be preemptive!

We have trap crops! But for my kind of setup, I doubt if I could have space for sacrificial dummies :) I think restarting is a great chance to improve my trellis too ! Will post more pics in 37 days !

I'll re-pot too!

Thanks a tonne!

rainbowgardener wrote:You've gotten really good advice already and I don't have much to add. But it looks like the soil in your pots probably settled. They could all use to be "topped off." Not only does that give the plants more soil to draw from, but especially for young ones like the eggplant, it keeps them from sitting down in the shade and air circulation barrier of the pot.

But top off with whatever potting mix you were using in the rest of the pot. If your soil is clayish, as it looks, spreading a layer of that on top of your potting mix just acts like a seal.

Personally, I wouldn't put any garden soil in smallish pots like that, just fine-textured compost, the coco-fiber, and some of the kinds of things applestar was suggesting for keeping air and water channels, which could also be perlite, rice hulls, crushed lava rock, etc.

Nothing much that you spray on the leaves will take care of leaf miner larvae, which are protected inside the layers of the leaves. Just pull the leaves or the part of it with the critter in it as applestar suggested and dispose of it.

For future reference if you can find lambsquarters, columbine, or velvetleaf, they are good trap crops for the leaf miners. Lambsquarters is a common weed [where I am]. Velvetleaf is a wildflower. Mine came from a packet of mixed wildflower seed. Columbine is a very pretty shade plant. I have velvetleaf that pops up around my property ever since I planted the wildflower seed (everything else died out). The leaf miners love the soft leaves of the velvet leaf and leave everything else alone. I just have to keep pulling the squiggled leaves off the velvetleaf.

I don't know if any of those grow where you are, so you might have to ask around if there are local plants that work as trap crops for them..

imafan26
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I don't worry too much about leaf miners myself. By themselves the damage is mostly cosmetic. They are the larva of flies. Squishing the larvae in the leaf does work, but it is really hard to catch the adult flies. I would not use systemics on anything I eat. However the trap plants are a good idea and I have used fine netting, tulle from the fabric store as a barrier against fruit flies and that could also work against leaf miners.

The hole in the bitter melon and the caterpillar you found may be pickle worm. It is a common problem of curcubits. Physical barriers do reduce the damage. We make a tube by folding a sheet of newspaper about a foot long and 9 inches wide into three equal sections. The young fruit (a couple of inches long) is wrapped in the newspaper tube. The top is secured with a skewer, the bottom is left open. Newspaper will need to be replaced if it gets wet. Other ways to protect fruit would be with a paper bag or fine netting bags or paint filters bags from the paint store. I make fabric bags out of tulle to protect individual fruit. They dry quickly when they are wet and I can see the fruit ripening inside the bag. Down side, I still need to use bird netting because the birds will rip the bags to get at the ripe fruit, especially tomatoes.

https://utextension.tennessee.edu/publi ... s/W206.pdf

Next time place the curcubits out in the open and away from the wall and either plant fewer of them or space them apart more to improve air circulation. It will reduce some of the problems with the fungal diseases.

Your planting mix sounds like a good organic mix. I cannot use a mix like that because of the way that I water, it would be too wet for too long. But if you control the watering it can work well. I agree with Rainbow though that it could use something to help with aeration as that kind of mix will compact and decrease air space. Coarse Sand, or fine cinders are heavy but would be good for improving drainage. Perlite is lighter and works too.

I would also go with the biggest pots I can get. I prefer to plant in 20 inch pots they are less prone to drying and falling over in the wind and tomatoes and eggplant have large root systems. I can also plant a bout 6 cucumber or bean vines in a 20 inch pot and still plant lettuce in the pots when the other plants are still small. I find that plants that I have in pots on the cement sidewalk get a lot of reflected heat and dry out faster than pots sitting on dirt or on black mulch. To keep the sidewalk plants from overheating and because I have some escapees, I will double pot them, placing the planted pot inside a larger pot or group the pots close together to insulate them and with black or red mulch plastic under them. I don't move my pots much once they are planted, but if I have to, I have a dolly for them.

You have a nice roof garden going.

n00bgardener
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Nice idea on the net.. Pickle Worm - this guy had proper hair on it.. and he died due to the neem spray (took time though). Those plants are growing bad every day.. one cucumber looks like a round bottom flask. I'd rather cull them, that's the penalty for being so reckless ! I have a question for you. does the news paper trick you unfolded in your comment below make the cucurbit long and thick? Nice comment on the reflected heat.. maybe my black pots need to be painted white..
imafan26 wrote:I don't worry too much about leaf miners myself. By themselves the damage is mostly cosmetic. They are the larva of flies. Squishing the larvae in the leaf does work, but it is really hard to catch the adult flies. I would not use systemics on anything I eat. However the trap plants are a good idea and I have used fine netting, tulle from the fabric store as a barrier against fruit flies and that could also work against leaf miners.

I think I will post up photos of the root anatomy after I un-pot the cucumbers and bitter gourds. I plan to do it on saturday or before - lets see.
imafan26 wrote:I prefer to plant in 20 inch pots they are less prone to drying and falling over in the wind and tomatoes and eggplant have large root systems. I can also plant a bout 6 cucumber or bean vines in a 20 inch pot and still plant lettuce in the pots when the other plants are still small.

THANKS A TONNE !



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