Before you go straight to fertilizing, take a moment to rule out overwatering (damp yellow) or lack of water (crispy or dead). Next look at the foliage for signs of disease or insect damage. Could there have been a drift from a weed killer that might be distorting the foliage? With those things in mind, check for signs that nutrients are lacking. Here’s a helpful guide:
- Light green foliage and yellowing mature foliage can be a sign that a plant needs nitrogen.
- Chlorosis (light green leaves with dark green veins) can be a signal that a plant needs potassium.
- If older leaves are turning purple at the base and other leaves are dull, dark-green, there could be a deficiency of phosphorous.
If none of these fit the bill or if you’re not sure, a soil test can help answer questions about missing nutrients. As always, ask your local garden center professional for guidance in selecting the best fertilizer for your soil and plants. That’s what they’re there for!