Fertilizer recommendation

[kimmyB]

Hey Everyone !

First day on the forum so let me know if I don't do things the right way.

I'm not super new to orchids (3ish years now) but my collection has expanded a bit over the past year. I've been using the MSU fertilizer from repotme and many of my orchids my older ones in particular) seem to like it (on the rest, I haven't noticed much difference but that could be because I haven't had them long enough.

However, my wallet is honestly hating me at the moment so I'm on the market for an alternative. I know quality isn't cheap (and I'm not trying to cheap out on my babies, I swear lol) but I'm hoping someone might have a recommendation for a fertilizer that has worked for them that might be a bit kinder to the wallet than repotme.

My follow-up/bonus question is whether I should continue using tap water (we get ours from the Tennessee river and it's worked well so far) or switch to filtered water. I've been considering switching but was wondering if there are any potential downsides to doing so.

[estación seca]

Welcome to the Orchid Board!

Proper temperatures, humidity, light and watering are far more important than fertilizer for most orchids. Until all those are in the good range, I don't think fertilizer composition matters much, so long as it contains the needed macro- and micronutrients. When cost is an issue, I think people can grow most orchids fine with relatively inexpensive powdered 20-20-20 with micronutrients. I get it at an agricultural supply company here. A 50 pound / 23kg bag costs less than 5 pounds of MiracleGro at a garden shop. You can use it on your outdoor plants, too.

Get your water utility's water quality report online, and look up the mineral content of your water. It is probably quite low. I have friends living on the Tennessee River in Alabama, and their water contains very few minerals. It is great for orchids.

[camille1585]

Welcome to Orchidboard!

As ES states, fertilizer is going to be the least important of the growing factors given that the nutritional needs of orchids are so low. I use MSU fertilizer now, but before that I used 'standard' fertilizers such as 20-20-20. The strength of the fertilizer doesn't matter as you can adjust the dosage to give the right amount. (If you don't know how, Ray's calculator is a useful tool: Nitrogen Management Calculator › First Rays LLC)

Do you know what the quality of your tapwater is? If it's rather pure, and low in calcium/magnesium, then you would need to supplement a basic NPK fertilizer with something such as CalMag.

Another option would be to buy your MSU fertilizer somewhere other than repotme, I'm sure other US based members would have some suggestions for you.

Filtering your tapwater changes nothing for the orchids. Filtering generally removes chlorine and other chemicals, but the minerals present in the water will stay the same. What are your concerns about tap water quality?

[Orchid Whisperer]

Hi kimmyB

I agree with e s., that you should check your local water utility report for minerals. I suspect it will confirm what to your orchids (and e.s.) have told you, your water is fine for orchids. The Tennessee River travels over a lot of country, a lot of it underlain by limestone and other rock with beneficial Ca and Mg.

Your Repotme MSU fertilizer should last you a while, since orchids only need weak and infrequent fertilizer. Most big-box home improvement stores (like Lowes or Home Depot) will have orchid fertilizer in the garden section, any brand that supplies N, P, and K should be fine. Your tap water probably supplies a lot of micronutrients, so even a general purpose water-soluble fertilizer should be fine. Just use less than what the package recommends (1/4 of the recommended strength should do it).