Backyard Aquaponics
A place to discuss aquaponics

Get some pretty bad blossom and end rot on some of the crooknecks. I understand calcium is the solution so I picked some up at the garden center and added a few cap fulls. Can anyone advise on how much should actually be added and would the be a benifit to actually spraying the plants?

I would say spraying would probably be more effective. Blossom end rot is a calcium deficiency in the fruit but rarely is it actually caused by a calcium deficiency in the soil (or whatever the plant is growing in.)
In soil grown or container plants it is more often a problem with the roots having trouble taking up the calcium, usually because of uneven watering and the roots drying out and being stressed. Other times the plants just grow so fast that the plant is unable to get enough calcium up to the fruits fast enough as they are developing. Either way, spraying is more likely to help the plant produce better fruit in the future.

Just so you know, the fruits that are already affected, won't recover, best to just remove them. With the weather there getting hot, be sure you spray in the evening so that the plant won't get scorched by the heat of the day right after being sprayed.

Now I don't know the situation with your source water or your pH but I kinda doubt calcium deficiency is a common problem in AP system calcium carbonate is used to keep pH buffered or if you have hard water, you already probably have quite a bit of calcium in your water. But if your pH is low, then adding some calcium carbonate to buffer you system should help both situations. Shell grit, garden lime or even a hand full of limestone pebbles should have some effect.

PH is actually a little high 7.4 on both low range and high range tests. I will try a spray.

So I pitched a couple of fruit that were rotting - lost of rotten blossome too. Lost count of those though. Then I gave it a good spray of calcium.

There is also a bit of mold growing on some of the leaves. Should I do anything about it?

How often should I spray? I'm thinking nightly until the leaves seem to regain some color.

When you say mold, do you mean powdery mildew? I usually ignore it but there are plenty of home made recipes that are supposed to improve it. I've heard that powdery mildew tends to attack plants that are suffering form potassium deficiency so a dose of maxicrop might be in order. I've never had very much luck with cucumbers or any squash in my AP system and I always figured it had to do with my high pH and Iron lock out. With the cucs they often get started ok and even produce a few fruit before dieing. The few squash I tried in the system would suffer extreme powdery mildew and blossom end rot before I pulled them out.

I can usually grow lots of the plants in that family just fine in dirt here (well actually huge mounds of mushroom compost on top of my sand with drip irrigation) so I haven't put too much effort into trying to grow them in AP. Powdery mildew still attacks them but I generally still get enough production that I don't bother trying to treat it, I usually just figure it's the climate.

Ya - just a powdery looking mildew that dots the leaves a little bit. I misted with calcium several times last night. Still some blossom rot this morning, but noticably less. And no more end rot that I have seen. The dirt garden ones were showing signs also, so I misted them as well, but they are not really fruiting, so I might just pull them out. The AP squash are just so big, I will keep them going even if the blossom rot continues unless someone has a reason not to...they are keeping the water nice and clean.

Hey Mark -
Are the powdery spots getting bigger? I Googled for images and each one looked a whole lot worse than yours. Total leaf coverage. Methinks you are catching it early...

And the little black specks are part of the disease's life cycle. I'm studying it in more detail now; I would remove the leaves with the white stuff and discard away from either garden. Still reading to find out what's best to remove the black flyspecks ("which came first, the powdered sugar or the pepper?").
I have a Houston-specific gardening book that may have a safe specific treatment too.

Rick

No - the powder does not seem to be getting much worse. I have seen it in both the dirt garden and AP squash. I came home today and the squash in the dirt garden are history. The heat is just to much for them now as they get no shade at all. I watered really well last night to, but they are all wilted and laying on the dirt. So I plucked the only decent sized squash for a grand total of two out of the dirt garden. There are still plenty in the AP though. I will mist again with calcium tonight - it could justy be they are being attact because they are weak. The growth is still really implressive though. I plucked another squash out of the AP system also - looks fine.

I really think the pepper is some sort of bug poop...while nothing seems to be eating the squash, the radishes are getting decimated by something.

Let me know what you find.

Mark

Radish is usually more of a cool weather crop so if they are getting attacked, they are probably suffering from the heat too. Of course I let a couple radish plants go to seed a few years ago, they got scary big and survived right on through the summer into fall.

Scary big is an understatement! They arn't as big as the squash - but impressive non-the-less. I wanted to let these go to seed too and practice collecting the seeds. It is SO funny the couple people that have asked what they are.

Something is actually eating them though - they seem to be OK in the heat...I am finding some sort of flying insect that seems to be atracted to them...small like a fruit fly. But no catapillars that I would normally atribute this damage to...strange.

Back to the end rot - found another rotten squash and pitched it. Keep pulling blossoms off too. Seems like an endless supply of rotten one. I will keep dosing with calcium and added some iron also as the leaves are a little splotchy also. I like what you said about the excessive growth - it makes perfect since as these things are growing SO fast it is amazing! In fact some of the "branches" have broken under their own weight hanging over the edge of the growbed. And several new shoots appear every day...at least 10 maybe 20 new little buds every day also....I keep saying slow down Nelly - but she just wont! The growbeds are totally over taken by the squash, not sure any of the other stuff will survive. And there was only six of them in the one growbed - but it has spilled over and is covering most of the second growbed now. Noone will ever be able to convince me that this is not the absolute best way to grow veggies!