manganese sulphate dosage for a sago palm in a 16" x16" pot?

[BetsyS]

What is the manganese sulphate dosage for a sago palm in a 16" x16" pot? Fronds are 2-4 ' long.

 

 

[Than]

How do you know when a plant need manganese?

[GeneAZ]

I've used 2 teaspoons of 31% manganese sulfate in a 2-gallon watering can once in spring, once per year.  Haven't used manganese sulphate.

[Fusca]

3 hours ago, ego said:

How do you know when a plant need manganese?

Not sure about other plants but Cycas revoluta will get yellow spots on its leaves when it needs manganese.

[PalmsandLiszt]

Your sago look perfectly healthy to me. Also, my understanding was that an overabundance of Mn can interfere with Fe uptake, so I'd only apply a fertiliser balanced in micronutrients unless the plant is showing clear symptoms of Mn deficiency.

[Merlyn]

I use Rite-Green brand manganese sulfate.  It's very small hard beads, about the size of a BB.  For trunking plants in the ground I generally give them about one handful per plant.  This probably dissolves and washes away a lot faster here in swampy Florida than it would in a pot.  We get daily afternoon thunderstorms of up to an inch of rain at a time.  I'd *guess* a reasonable dose is maybe 1/4 handful or a couple of tablespoons?  I zoomed in on your photo and don't see any signs of "frizzle top," or other yellowed/browned leaflets.  At this time I'd think it doesn't really need any manganese.  If you wanted to give it a small amount to avoid any issues later, maybe 1 teaspoon of granular should be safe.