Reasons for gardenia leaves yellowing: soil becomes alkaline, soil plate is not breathable, lack of iron element, lack of magnesium element, fertilization is too much and too thick, watering is too much, light is not right, frostbite.

1, soil becomes alkaline

Gardenia is like acidic soil plant, if potting soil pH is alkaline, it is easy to happen yellow leaf phenomenon. Northern soil and water, many areas are alkaline, and contains salt is relatively high, long-term growth in this environment, easy to lead to plant yellowing, will eventually affect the flowering.

2, the soil slab is not breathable

Gardenia like loose breathable soil, if the soil viscosity is too heavy, or the breathability is poor, also easy to lead to the yellowing of the leaf body.

3, lack of iron element

Gardenia's demand for iron is relatively high, if lack of iron, gardenia new leaves will first yellow, serious leaf veins are yellow or white (iron is not easy to transfer, so the old leaves are generally green).

4, lack of magnesium

If it is lack of magnesium, the old leaf will be yellow, then the new leaf is yellow, the leaf veins are still green.

5, too much fertilizer too thick

Fertilizer generally to thin fertilizer, if too much fertilizer, or a fertilizer is too thick, easy to burn the roots resulting in yellow leaves, or even plant death. The general performance of the new leaves appear brown at the top, the old leaves scorched yellow and fall off.

6, watering too much

Gardenia must not frequent watering, avoid stagnant water, may lead to rotten roots. At this time generally young leaves begin to yellow, old leaves no obvious change.

7, improper light

Some will appear yellow spot. Also not long-term shade, or the plant is prone to defoliation and yellowing.

8, frostbite

If the temperature is too low, the gardenia may also have frostbite, resulting in yellowing leaves.