Ludwigia arcuata

[beeky]

I have some L. arcuata which is growing really well and has redder leaves at the top which get redder towards the tip. I assumed this was just the plant colouring but I noticed last night that the leaves with the most red are starting to look almost like they're drying out. Thinner and kind of curled at the edges. None have fallen off, but wondered if anyone has seen anything similar on this or other plants.

It's in a 3' tank, 18" high lit by 2xT5s. 36w each I think. No NPK is dosed, but trace is, with DIY CO2 and easycarbo every other day. Possible NPK deficiency? The reason there's no NPK is because I was dosing Flourish thinking it was a full fert, but then found out it was only trace.

I'll try and get a photo up tonight.

Cheers,
Graham

 

[Wolfenrook]

It's most likely red at the tips because these are getting more light than the rest of the plant, red plants mostly like light and plenty of it usually. With more powerful lighting you would find that the red was further down the plant as well, the leaf shape is probably related to the lighting as well.

I doubt it has anything to do with your not dosing NPK, unless there is a really serious deficit of this (eg you live in a soft water area).

Ade

 

[George Farmer]

NPK will improve things, no doubt.

 

[ceg4048]

Graham,
Let's see the photos. L. arcuata and some other red plants can show more red as a result of N deficiency stress. Some hobbyist use this NO3 attenuation to get more red expression. But you haven't reported any BGA so N might be low but not low enough for BGA.

Severe chronic and, sometimes, acute K deficiency stress can cause necrosis progressing from the leaf edge to the midrib as the stress increases. As the deficiency progresses, most of the interveinal area becomes necrotic, the veins remain in it's original colour and the leaves can curl and crinkle.

Chronic P deficiency would result in general dwarfism tank−wide, but you would have already seen indications of this via the appearance of GSA.

It's not clear what your NPK content is because it depends on your water supplier as well as feeding patterns and waste accumulation. We also need to get a better idea of which leaves are suffering this drying out − new leaves or mature leaves? Since you are dosing traces we might assume for the moment that these are OK but Ca, Mg, S as well as NPK and even C could be contributing factors.

What about the green plants? They might give us a better indication. Are any suffering chlorosis or some form necrosis?

Cheers,

 

[beeky]

Thanks for the replies.

The most affected seem to be the more mature ones, although the very mature ones that existed before I got it still look 'normal'.

I'll get photos up when I can. I didn't have time last night as I spent 3 hours mowing the lawn :?

 

[beeky]

On reflection I think I'm probably just being a bit paranoid as other photos I've seen don't look dissimilar. Anyway, here's a pic:

I think the leaves have blackended very slightly on the edges which first made it look like they were curled, but I think I'm looking too hard!

 

[ceg4048]

Gosh, it looks OK to me. the leaves on this plant are so needle-like it's hard to tell so that's why it might be better to asses the broader leaf green plants.

Cheers,

 

[beeky]

Thanks Clive. I'll be able to sleep again tonight....

 

[Dave Spencer]

Mr Amano uses L. arcuata a lot, and his look similar.

Dave.