Easy plant care for the brownest of thumbs

Having a "green thumb" I've found for the most part is fairly easy. All I really do is know what category the plant is in and then take a very general approach of maintenance to it. I'm sure that plenty of people are extremely particular about temperature, placement, light, shade, feeding, pot size, soil type and all of that but for the most part you can get satisfactory results just knowing and doing a few very basic things.

Know the 4 most important categories of plants

There are many specific types of plants but I like to group them into 4 main categories.

Succulents and cacti:
Obviously a cactus
Has thick or waxy leaves
Is potted in sand & rocks when you buy it

African Violets and Orchids:
Are typically potted in bark mixtures
African Violets have soft, fuzzy leaves and bloom in the center of that
Orchids tend to have longer, woody stems, have a shoot that flowers and almost always are tied to a stick to keep from falling over
Orchids also can have very exotic-looking flowers.

Regular Houseplants:
Anything with lots of green leaves that's potted in dark soil.

Other exotic and high-sunlight plans:
Low amounts of green on plant
Less leaves

Sunlight

Placing your plant in a spot where it gets good sun exposure is key. If you don't have much or any direct sunlight, you are limiting yourself to a small number of low-light plants, and I've found even those don't do that well with only indirect light year-round. I have eastern exposure where I live and get quite a bit of sunlight through the windows. I keep all my plants located in spots near the windows where they receive plenty, and I rotate them every month or so to keep them growing evenly. There are some low-light plants that burn if kept in too much light and heat for too long. You'll see it if it happens and all you have to do is move them to a spot with less exposure.

So far as I've seen with most people suffering from plant problems, the biggest problem is that their plants just aren't receiving enough sunlight. If you're having problems with slow plant growth, poor plant health or you're finding that after watering the soil isn't becoming totally dry within a week, you may have too little sunlight.

Water

Most plants do well being watered thoroughly about once a week. If you've just re-potted a plant into a bigger pot, don't saturate the water. The balance is supplying the plant with a good amount of water while not rotting its roots. The roots WILL ROT if allowed to stay wet for too long. My rule of thumb is to let the soil get very dry before watering again. You can tell when it's dry either by touch or by picking up the pot. It will be noticeably lighter. If you've just re-potted, you may want to give a little less water than would regularly fill that amount of soil because the roots haven't grown into it yet, and it can't all be absorbed that fast.

Cacti and Succulents should be left dry for about 3 weeks before watering. That means if you water it and it takes a week to dry out, wait another 3 weeks before watering, so once a month. There are exceptions to this rule, but I've found that with jade plants especially, this is key to the plant staying healthy and not rotting away.

Food

There are many kinds of plant food for many different purposes. If you get a general purpose soil and re-pot your plants every year or so, it won't be necessary to add additional fertilizer. Properly fertilized, your plant generally will grow bigger and faster than otherwise, however it is easy to overdue it. There is such a thing as too much food for a plant and it will harm your plant. Also, all fertilizers are not made equal. Not only do they come in different formulas (such as 15-3-15 vs 10-10-10), but they're derived from different materials that may make them metabolize faster or slower depending. I prefer 3-part fertilizers made from salts. I've had many problems with "organic" ones (from guano and other sources) due to slow, multi-stage metabolism. Unless you really know what you're doing and are willing to lose a few plants experimenting, I'd say stay away, or use VERY sparingly.

Potting

As the visible part of the plant grows, so does its roots. Most will continue growing until there is absolutely no space left for the roots in the pot. At this point the plant can't really grow much more on top because it is what is called root-bound. If you want the plant to get bigger or just want to keep it healthy, it's time to move it to a larger pot. Most plants can use regular general-purpose soil. There are special mixes for Cacti & succulents, and then for orchids and African violets. When re-potting anything but a regular plant, you may want to consider putting a thin layer or sand or gravel on the bottom to allow the water to drain out easier. Don't use large rocks or put too much drainage in or the plant won't get enough water. A half inch or so will do fine.

To actually re-pot the plant, prepare the new pot by putting a small layer of soil on the bottom, using enough to put the plant where you want the top of the soil to line up on it's stock. For plants that grow up and stretch a lot, I try to replant them down a bit so that some of the stock that was above soil is now below. It will grow new roots out of that spot eventually. Make sure your plant is DRY before removing from its pot. It's very, very hard and unsafe to do wet. If pulling from a plastic pot, just work your hands around the sides squeezing a little bit. This will separate the roots and soil from the sides. If using a regular pot, try turning it upside down and shaking the pot a big while holding your hand on top of the soil to catch the bundle when it falls. If the plant is absolutely stuck, use a butter knife around the edge, being careful not to cut any roots.

(Removing half-dead spider plant from old pot)

After it's out, just put it into the new pot in the position you'd like and fill with new soil. Always use new soil. If the old pot looks white or crusty, throw it out. It's molded and will likely harm any new plants you put into it. Tap the soil down gently. The amount you pack it now is going to determine how much water it will hold and how well the water will drain. If you pack it down tight, it won't drain well and will likely make for a difficult first few months for the roots. If you don't pack it down at all, the water will flow right through and you won't get good absorption.

(Spider plant re-potted. It will look MUCH better in a few weeks.)

(Jade and Aloe in new pots)