If your Pygmy palm has yellowing leaves, this may be due to something as simple as the tree's natural growth cycle, or a more serious concern like a vitamin or water deficiency. Check your palm's symptoms to determine the problem.
Consistent yellowing of your Pygmy palm's older fronds may be a sign of nitrogen deficiency. To correct, add a nitrogen fertilizer or a nutrient-rich organic compost. If the new, smaller leaves on the Pygmy are yellowing, a lack of iron in the soil may be the culprit. Regular mulching and iron chelate application will re-balance the iron levels.
Over- or Under-watering
If your Pygmy palm is over-watered, the soil becomes more susceptible to fungal diseases, which may cause yellowing. Check that your palm's soil is aerated and has plenty of drainage room. According to the website TreeHelp.com, under-watering may also cause yellowing, as the warm-weather palm requires plenty of hydration.
Natural Growth Cycle
Your Pygmy palm's growth cycle will naturally result in yellowing leaves as the tree's older leaves are replaced by new, green fronds. Determine the growth stage your Pygmy palm to help decipher if the yellowing is normal.
Pygmy palms thrive in the USDA's hardiness zones 10 and 11, which include southern Florida, Arizona and coastal California. If you live in a climate with temperatures that regularly dip below freezing in the winter, your Pygmy palm may not be suited to the environment.