foliar feeding on potted Beccariophoenix alfredii and understory palms

Hi everyone,

I’m looking to hear about your experiences with foliar feeding on palms, especially regarding species-specific quirks or sensitive new growth.

Here is my current situation: I’m growing 5-year-old Beccariophoenix alfredii in pots (approx. 30 cm / 12" pot diameter for a 60 cm / 24" canopy) on a south-facing balcony (part-shade). The soil is well-drained, and I use soft tap water.

The newest emerging fronds have been coming out very pale / light green, while the older fronds remain a healthy, dark green. Nitrogen deficiency can be ruled out, as well as root-binding.

Since the soil and watering seem fine, I suspect a trace element imbalance — specifically a relative Manganese (Mn) or Iron (Fe) uptake bottleneck during fast summer growth.

I’m using a high-quality specialty palm fertilizer (RPS), but to bypass any potential root/substrate absorption barrier, I’ve decided to start a foliar feeding regimen:

• Sprayed at dusk / late evening to prevent leaf burn.

• Applied at a diluted rate (approx. 1/4 of the recommended soil dosage).

• Focused on the undersides of the fronds and the emerging spear.

My questions:

1. Has anyone here successfully treated pale new growth on Beccariophoenix alfredii (or similar species like Dypsis / Archontophoenix) using foliar sprays?

2. Did you use a standard chelating micro-nutrient blend (EDTA/amino acids), or did you need a pure Manganese spray?

3. Is foliar feeding also a good idea for my tropical understory palms? Kerriodoxa, Joey, Calyptrocalyx...

Thanks in advance for sharing your insights and experiences!

Best regards,

Matti

PS: The last post I found about this topic is 16 years old...