Temperatures and Semi-Hydro

[bench72]

Hi Everyone,

So, before I jump in and put half of my plants in semi-hydro, is it very important to make sure that temperatures do not go below 50f (10c)?

A number of my plants are outside where the temp cannot be controlled and well, it can get pretty cold out there in winter, ie prolly around 40f (4c). At the moment, the plants seem to manage the cold temps because I tend to make sure that they are dry when night falls or during really cold days. But with s/h won't the roots stay 'wet'? Will this cause problems like root rot, etc, etc?

Cheers
tim

[uncasteeb]

I have a Den kingianum in s/h & this has spent the last couple of months in my bedroom window with no heating , so the temps do get to about 32f.
If you have to water the plants tip the water out after it has had a chance to wet the medium & leave the res basically dry.Well thats what i do .

[bench72]

Sweet, Thanks for that Uncasteeb.... and I'm glad you used Den kingianum as an example coz most of the plants outside are Dendrobiums.. looks like I will be heading to the hydroponics shop for supplies.

cheers
tim

[bench72]

well wasn't sure where else to post this, but I figure this may be as good a place as any. Here are my two first attempt at semi-hydro.

One is a phalaenopsis tetraspis and the other was a paph venustum (who said this was an easy plant to grow?). Both plants were suffering from too much water and consequently had lost most of their roots, ie they both only had one root each.

Anyhooo, as you can see the plants are tiny seedlings so the size of the home-made (read "burned holes @ home") pots are kinda maybe a bit too big for them. Is this gonna matter too much? The hydrogran pellets seems to be staying wet/moist even on top, ie after almost two days, this is good right?

well that's enuff for now.. no doubt I'll have more questions to ask...

cheers
tim

[uncasteeb]

I have a Paph venustum in s/h & it,s growing really well but mine is multi-growth so a lot bigger than yours.I used a taller pot so the top does dry out , also i have quite strong air movement which may dry the top layer out .
When i decided how high the res had to be i let the roots hang down straight & put the res in just below the end of the roots.Watch fertilizing the P. venustum as it does seem to be slightly prone to leaf die back(tips turning black & then the black gradually moves further down the leaf).

[bench72]

Hi uncasteeb,

funny you mentioned the fertilising and leaf die back... since posting previous message, and after waking this morning, I noticed a dry brown spot on one of the leaves. When I first watered the plants I used water mixed with a 'hydroponic fertiliser' at half strength. Maybe the whole thing is too much of a shock to the little tyke... Will try and flush the medium with water and hope that removes the leftover fertiliser.

cheers
tim

[Cinderella]

Tim, when I have a tiny seedling and want to use s/h, I use one of those plastic drinking cups, suggested to me by another fabulous Forum member. I burn holes in the bottom using a heated nail, about an inch or so from the bottom. Works like a charm.

[bench72]

geepers, that's a great idea.... that would be so much better in terms of space as well... I don't think I could have put all my plants in s/h if they were gonna take up so much space... thanks Cinderella

cheers
tim

[uncasteeb]

Another good s/h pot is plastic pint glasses.

[Slipperhead]

I just had a good case of leaf die-back on a nice phrag. The tips burned so I cut them off at an angle. Then the cut tips begin to die and the whole thing began to move down the leaf. I soaked and flushed and soaked and flushed the media (s/h) with clean water to wash out mineral buildup, fertilizer, etc. The die-back seems to have stopped. I'm almost convinced that it was too much fertilizer...hence, fertilizer burn that I was seeing.

This plant drinks water much faster than any other plant I own. I was continually topping it off with 1/2 strength fertilizer every other day or so! WAY too much in my opinion. We'll see what happens but it is looking like the burn has stopped. I'm keeping my fingers crossed! I have not had fertilizer burn with any other plant. I am now religious about fertilizing weekly (that means Mondays) at 1/2 to 1/4 stregth!

I'll supply a photo is anyone is interested.

I also had a small paph seedling not long out of flask submit to classic "damp-off". It turned brown at a leaf tip, started on another leaf, and the plant was toast in 3 days. This plant was in a short pot and was not getting any kind of air circulation. Perhaps if I had seen it early enough I could have treated it with cinnimon, Physan, etc. and saved it!

I'm having trouble maintaining decent humidity inside the house with these dry days!