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lmecheverri

mold-looking layer over potting mix

3 years ago

I have discovered what appears to be a thin layer of mold substance over the potting mix. All I put is water and only once few weeks ago I added coffee grinds and coffee water. Any thoughts?

Comments (4)

  • 3 years ago

    the coffee grounds are rotting.. and mold is a biodegrader..


    scrape it out with a teaspoon.. or bare root it and repot it..


    and throw your coffee grounds otuside... not in a pot.;. and no banana peel in a pot.. or anything else you can dream up ...


    regardless.. its rather benign.. and i doubt its going to harm the plant...


    ken

  • 3 years ago
    last modified: 3 years ago

    I'd suggest you stop with the coffee or tea, the beverage and the solid grinds. Something I wrote to explain why:

    Coffee/Tea Grounds

    Forum discussions frequently center on the question of adding dilute coffee/tea or grounds to plants as a 'tonic', but Arabica (coffee) and Camellia (tea) are known for their toxic alkaloid (caffeine) content and their allelopathic affect on plants as well as autotoxic (poison to their own seedlings) effects on future generations. Caffeine interferes with root development by impairing protein metabolism. This affects activity of an important bio-compound (PPO) and lignification (the process of becoming woody), crucial steps for root formation.

    We also know that the tannins in both coffee and tea are known allelopaths (growth inhibitors). There are ongoing experiments to develop herbicides using extracts from both coffee and tea that cause me to want to say they might serve better as a nonselective herbicide than as a tonic. I would not use either (stale coffee or tea) by applying directly to my plants - especially containerized plants; nor would I add tea bags/coffee grounds to my container soils.

    The fungal hyphae you're seeing are very likely not an issue. In some cases, the presence of fungal fruits or hyphae can be a symptom of over-watering, but more often it's not. Plants live in harmony with thousands of species of fungal soil dwellers without issue. In some cases, the plant and fungi actually form a symbiotic relationship where living together offers an advantage to both plant and the fungi. Try to be careful about your watering intervals. Wait until the soil is starting to dry near the pot bottom.

    You can easily establish appropriate watering practices by using a "tell" , a simple tool you can make from a $2 wooden dowel rod (1/4-5/16 diameter) you can but from any hardware or builder's supply store.

    *************************************************************************

    Using a 'tell'

    Over-watering saps vitality and is one of the most common plant assassins, so learning to avoid it is worth the small effort. Plants make and store their own energy source – photosynthate - (sugar/glucose). Functioning roots need energy to drive their metabolic processes, and in order to get it, they use oxygen to burn (oxidize) their food. From this, we can see that terrestrial plants need plenty of air (oxygen) in the soil to drive root function. Many off-the-shelf soils hold too much water and not enough air to support the kind of root health most growers would like to see; and, a healthy root system is a prerequisite to a healthy plant.

    Watering in small sips in order to avoid over-watering leads to a residual build-up of dissolved solids (salts) in the soil from tapwater and fertilizer solutions - which limits a plant's ability to absorb water – so watering in sips simply moves us to the other horn of a dilemma and creates another problem that requires resolution. Better, would be to simply adopt a soil that drains well enough to allow watering to beyond the saturation point, so we're flushing the soil of accumulating dissolved solids whenever we water; this, w/o the plant being forced to pay a tax in the form of reduced vitality, due to prolong periods of soil saturation. Sometimes, though, that's not a course we can immediately steer, which makes controlling how often we water a very important factor.

    In many cases, we can judge whether or not a planting needs watering by hefting the pot. This is especially true if the pot is made from light material, like plastic, but doesn't work (as) well when the pot is made from heavier material, like clay, or when the size/weight of the pot precludes grabbing it with one hand to judge its weight and gauge the need for water.

    Fingers stuck an inch or two into the soil work ok for shallow pots, but not for deep pots. Deep pots might have 3 or more inches of soil that feels totally dry, while the lower several inches of the soil is 100% saturated. Obviously, the lack of oxygen in the root zone situation can wreak havoc with root health and cause the loss of a very notable measure of your plant's potential. Inexpensive watering meters don't even measure moisture levels, they measure electrical conductivity. Clean the tip and insert it into a cup of distilled water and witness the fact it reads 'DRY'.

    One of the most reliable methods of checking a planting's need for water is using a 'tell' (more reliable than a 'moisture meter'. You can use a bamboo skewer in a pinch, but a wooden dowel rod of about 5/16” (75-85mm) works better. They usually come 48” (120cm) long and can usually be cut in half or in several pieces, depending on how deep your pots are. Sharpen both ends of each tell in a pencil sharpener and slightly blunt the tip so it's about the diameter of the head on a straight pin. Push the wooden tell deep into the soil. Don't worry, it won't harm the root system. If the plant is quite root-bound, you might need to try several places until you find one where you can push it all the way to the pot's bottom. Leave it a few seconds, then withdraw it and inspect the tip for moisture. For most plantings, withhold water until the tell's tip comes out nearly dry. If you see signs of wilting, adjust the interval between waterings so drought stress isn't a recurring issue.

    Al

  • 3 years ago

    I saw your like. How did you read all that so fast?


    Al

  • 3 years ago

    Speed reading… it works…