📊 Crop Data
🌿 Overall Status
Vitality
Diet
Foliar
Risk
!
Your petunias look full, leafy, and still actively growing, which is a good sign. The overall plant mass is strong, and I can see fresh growth at the top. The main thing standing out is the yellowing pattern on some leaves, especially the newer-looking leaves in the close-up.
⚠️ Observations
The yellow areas are showing up between the veins, while the veins stay greener. That pattern usually points to a nutrient uptake issue, not a disease. In hydroponics, this often happens when the plant is getting enough feed on paper, but something is limiting how well it can use iron, magnesium, or other trace elements. Your pH at 5.6 is a bit on the low side for petunias and can reduce uptake of some nutrients. The cool temperature, 16 C, can also slow uptake and make yellowing appear even when the solution is fairly balanced.
✅ Solutions
1. Check and adjust the nutrient solution to stay closer to pH 5.8 to 6.2 for petunias. A small rise may improve nutrient availability.
2. Consider a slight increase in nutrition if the plants are not already near full strength. Your 700 uS/cm is not high, so these symptoms may improve with a modest feed bump.
3. Use Hydroponic Nutrients if you need to fine-tune the base feed, because the yellowing suggests the plants may need better overall mineral balance.
4. If the yellowing continues on new growth, add CalMag Supplement carefully, since calcium and magnesium support healthy leaf color and nutrient movement.
5. Keep the reservoir and root zone well oxygenated with Air Pump if you notice slower growth, since cool conditions can make roots less active.
6. Since you do not control room temperature, monitor it with Thermometer so you can tell whether cold conditions are contributing to the yellowing.
If the newest leaves keep getting paler while the older ones stay green, I would suspect a micronutrient uptake problem first, with pH being the easiest place to correct.
🛒 Recommended Products
General Hydroponics Flora Series: FloraMicro, FloraBloom, FloraGro – 3-Part Hydroponic Nutrient
The Flora Series is a hydroponic-based nutrient system that helps fulfill your plants’ nutrient needs at every stag…
General Hydroponics CALiMAGic Quart
CALiMAGic 1-0-0 is a concentrated blend of readily available calcium and magnesium Prevents secondary nutrient d…
PH Up and Down (Two 1/2 Pint Bottles) 16 Total oz
Complete pH Control Kit – Includes solutions to raise or lower pH for balanced plant care. Supports Proper Nut…
Small Air Pump Aerator for 1-15 G Super Quiet 1.5 Watts, Complete kit
Unique air diffuser. Makes tiny bubbles, no bubble noise, give your fish a great supply of oxygen. Decorate your fish…
Govee WiFi Thermometer Hygrometer H5103, Indoor Bluetooth Temperature Humidity Sensor
Stay Connected Anywhere: With stable Wi-Fi and Bluetooth connection via Govee Home App, you can easily monitor temper…