|Three weeks ago I planted some herbs in containers inside the house. I watered them accordingly and fed them with liquid organic fertilizer made out of sea kelp. Before planting I also applied soil conditioner to the potting soil. But this week the base of the rosemary, peppermint and sage started to brown and also the tips of the leaves. I've
looked in some gardening books that I have but there is no reference about such disease.( It's been very cloudy and rainy in the last days also.) Can you help me?
|Rosemary is a Mediterrranean herb and enjoys alkaline soil, good drainage and hot sunny summers with cool, humid but sunny winters. Sage enjoys full hot summer sun and good drainage in the garden but does not need rich soil. It is usually winter hardy but still demands good drainage. The mints are winter hardy herbs but enjoy moist, deep, rich soil and part shade out of doors.
Basically, I think your three plants are begging to be outside for the summer. They all need good air circulation to thrive, and the sun lovers are craving the real thing. (Of the three, the rosemary is the most likely candidate for successful pot culture.)
Browning at the base and at the tips simultaneously is usually a sign of overwatering and/or overfeeding. Plants tend to balance their water and nutrient needs against the sun they receive, so less sun means less water and less nutrients needed. Since these plants are usually grown outside, you should try to maximize the amount of light they receive and cut back on the water and fertilizers until they reach a good balance. The rosemary and sage are both lighter "feeders" than the mint, so you might want to keep that in mind also.
Let's hope for a break in the rainy weather!