I'm new to the Dave's Garden forums, but have been using the website for years. This is by far one of the best plant websites online. I purchased a young coffee plant at a local garden center late last spring. Over the summer it did very well in part shade, but it has since struggled greatly after being moved indoors to a bright, southern facing window to overwinter. Although there were four or five coffee plants, only one survives now. The upper leaves still look quite good as do the bottom ones, but the middle leaves begin bleaching-out around the edges, going from a dark green to light green to yellow then brown. The patches grow from the end toward the stem, becoming crunchy and brittle until the leaf is dropped. I have had this problem every time I have tried to grow coffee, yet many I've talked too insist it is very easy to grow. I suspect it could be low humidity (its current location is in a bathroom however) or overwatering. Any comments would be much appreciated. I have posed several pics. Thanks!
What are you using for soil? Is the soil usually still moist when you water? What have you done about fertilizing over the last several months - be specific? Is it situated so it gets direct sun where it's sited now? Has it ever been repotted (as opposed to potting up), and how tight are the roots?
@ tapla It is currently potted in an 8 in ceramic pot with miracle grow African violet potting soil (I read that coffee plants are acidophiles) I've only re-potted once from the original 4 in plastic pot they came in shortly after I got them. They've been re-potted in the African violet soil for about 9 months now. Over the summer they seemed fine. They got several hours of morning sun when they were outside, now they mostly get filtered afternoon sun. I try to let the pot dry out before watering, but I get the feeling its not completely dry most of the time when I re-water. I have grown several coffee plant before and this always seems to happen independent of supplier, soil, location etc., which leads me to believe its an environmental or cultural problem.
Oh, I agree it's a cultural issue - there's little question about that.
Fertilizer? What are you using? how often? what strength?
Are you giving just enough water to moisten the soil or are you watering generously so a significant fraction of the water you applied exits the drain? The interveinal chlorosis indicates some nutritional issues that could either be resultant of fertilizing habits OR something cultural that is preventing uptake. The necrotic spots on the leaves are likely from a high level of dissolved solids in the soil (solution) or over-watering.
Your pots DO have drain holes & are not self watering? and we needn't be concerned that the temperature is dropping below 55* where you have the plants?
During the winter I usually back way off the fertilizer, but typically I use miracle grow diluted to about 1 tablespoon per 1 1/2 to 2 gallons. I would say it has been at least three months or more since I've last fertilized. The soil usually isn't waterlogged, but I try to water thoroughly (until water drains out of the bottom) and then let the top 1 1/2 in. of soil dry out before rewatering. The pot has one almost thumb sized drain hole at the bottom with a good layer of small stones to aid draining. I havent misted it or given it much other attention. I've seen this before, so I'm trying to figure out the cycle lol
@tapla Thanks for all your help, I really appreciate it. I've since repotted it with fresh, Citrus/Cacti Soil so that it helps keep water from hanging around the roots too long. I've also lightly fertilized with Miracle Gro diluted to the recommended level for houseplants, and put it up near a room humidifier in a southeast facing window. I'm hoping all this helps it take off again
If you were only allowing the top 1/2" of soil to dry before watering, the probability is high enough to be a near certainty that over-watering has been an issue. If you were using a commercially prepared, peat-based soil, it should be noted that almost all are excessively water-retentive to the point where they should be almost dry at the bottom of the container before the next watering. Using wooden skewers until you get a feel for what is the most favorable interval between waterings is a good idea. Insert the skewer deep into the soil; if it comes out dark/damp/dirty looking, withhold water.
Viewed as a group, most hobby growers have no idea how important soil choice is to the potential for their success as growers; and, of all the things we have any significant control over, choice of the soils we use probably has more sway over what we get back in return for our efforts than any other consideration. Using an appropriate soil allows you to work WITH the plant sciences toward healthier and more attractive plants, while an inappropriate soil choice always finds us battling against the limitations imposed by the very foundation of our plantings.
You're on the right track if you chose the soil you're using now with the thought in mind that you'll be reducing water retention, but my experience shows that most soils labeled as being for cacti, succulents, other specific plants, don't carry the concept far enough because the packages aren't willing to let go of a high % of fine particles in their soils.
Let me suggest some reading that will hopefully leave you with a better understanding of how important soil choice is to your success as a grower. I have helped thousands of people become better growers, and I can say without being the least bit bashful about it, that an understanding of how soils and the water/air they retain represents the largest step forward you can make at one time.
If you haven't read the 'sticky thread' at the top of this forum page, I think you'll find it helpful.