Water with plain water first before fertilizing?

[Girl_With_An_Orchid]

This is definitely a question I've had. I have always done a quick flush first and then soak in fertilizer for around 20 mins sometimes longer. The only times I don't soak are when its needed but I don't have time so I just do the flush. I think that the soaking allows the sphagnum to absorb enough fertilizer despite having been just watered and also makes sue that the bark doesn't get fully dehydrated. I kind of wonder whether that first flush is even necessary at that point though.

[K-Sci]

Originally Posted by Girl_With_An_Orchid

This is definitely a question I've had. I have always done a quick flush first and then soak in fertilizer for around 20 mins sometimes longer. The only times I don't soak are when its needed but I don't have time so I just do the flush. I think that the soaking allows the sphagnum to absorb enough fertilizer despite having been just watered and also makes sue that the bark doesn't get fully dehydrated. I kind of wonder whether that first flush is even necessary at that point though.

Flushing occasionally is a good idea when watering would otherwise be in too small a quantity to prevent fertilizer and hard water residues from building up in the pot. Flushing before soaking (submerging?) the pot every watering would also remove soluble residues. Unless the soak is in a very tiny amount of water the soluble residues, tannins, and other solubles in the bark will diffuse into the water during the soak and be tossed when the soak is done. Hence the brown coloration of the water. I can't think of anything a rinse and soak would do that either a good rinse or a soak would not already accomplish alone.

That said, when I grew indoors I found soaking for 15 minutes or more did wonders to keep my Phalaenopsis from needing a watering more than once per week (Besgrow bark, no sphagnum). With the much higher humidity in my greenhouse even large chunks of Orchiata are not hard to moisten with drench watering, (after starting them out with daily watering for the first two weeks or so). My orchids in moss would become waterlogged and never dry out if I soaked them once per week.

During my winter schedule I water with RO sprinkling from a water can daily (e.g. vanda with no media) twice weekly (mounts with moss, Neofinetia, & C. Walkeriana in jumbo Orchiata), or weekly (Cattleya and most everything else in LECA and Orchiata). I give all my orchids a good rinse once per month with (almost rock hard) tap water from a garden hose to remove solubles and give them a healthy dose of Ca and Mg.

-Keith