Vanda Blooming Problems
 

I have 7 vandas - all are kept outdoors on a screened in lanai in Naples, FL. Have had them a couple of years and they've previously done well but this year have struggled to bloom; several have sent out spikes that dried up and fell off before blooming. I water and fertilize once a week 7-9-5 alternating in a 3-12-6 once a month or so. Plants appear healthy with long root structures - they just seem to struggle blooming. Any suggestions on how to address this?

Are you saying that you water once a week? Vandas usually need to be watered more often than that. I water mine almost every morning but every other day would be alright also. I probably wouldn't use bloom and blossom on vandas. They grow continuously, even when they're blooming. I think bloom and blossom is more appropriate for orchids that have a growing season and a blooming season. I've also read that you want to face vandas so that the flat side faces the light. In other words the leaves should point perpendicular to the light. Just suggestions. Good luck.

Welcome to OB!

It does sound like they need a lot more water than your currently giving them.

Are they potted or in a basket?

I agree. Vandas like to dry out quickly but should be watered again before they are bone dry. If they get too dry they will abort a spike.

Thank you - all -for the suggestions and well-wishes.

The plants are all hanging in small baskets from the top of the lanai. No medium in the baskets. Roots drape down (and in one case are now over 6 feet long - it's nearing the ground now - should I trim them back at some point?) I will step up the watering as you suggest. Should I also increase the feedings from the once a week I've been doing or is once a week sufficient?

Once a week is fine but never trim off live roots.

I would water thoroghly daily and feed weekly. If the roots get too long to handle, you can always loop them back around in a bundle and tie the bundle. I would not cut the roots if you can avoid it. :)

vandas love to drink and they feed a lot...they like bright shady sun and warmth...the moment you let them feel temps below 50...they will sulk and go into life preservation mode and will produce a keiki but not any blooms(I have a humidifier and heater in Manhattan to give them constant 80F in the day and 65F at night)...they dont like the roots to be cut off...they take years to grow and the tips are the ones very sensitive to cold water(I water my vandas with tepid water from the sink with hose shower)...species bloom once a year(twice if youre lucky) the modern hybrids bloom as much as they can since they were invented for the cut flower florists ...once they are established in one place of the room and blooms...they will keep on blooming for you. Changing positions/light source, repotting and regimen will make them sulk on you.

Okay people, we all have to remember that there are no absolutes when it comes to orchid culture.

One of the best Vanda growers in the US walks thru his vanda houses in the Spring with hedge trimmers and cuts off the bottom third of the roots with no ill effects, on the contrary it actually encourages the roots to branch out and create more roots.