1. Water.
Here in the Sacramento Valley of California, the summers are dry and warm, thus watering about once a week in the greenhouse works out perfectly. The winters here are cool, but not that cold and the rain and clouds can set in for extended periods of time. Under those conditions, watering is light and only happens about once a month if even that. I’ve no idea how my watering routine would work if the greenhouse were located somewhere like Florida, New York, or Arizona. I could be killing a lot of plants if applied those guidelines to those areas. The point is that you have to pay attention to your plants and to your local weather.

One way of checking your plants to see if they need water is to dig down a little in the soil. If any plant is dry about 1 inch down, consider giving it some water. If getting that close to a prickly plant isn’t appealing, then use a screwdriver to dig down or purchase a moisture meter and poke the soil. Another way of checking water content is to hand weigh a pot before and after watering. It’s going to heavier after watering, but if you can kind of remember how light it was before watering, it will help give you an idea on when to do subsequent watering.

Over-watering is one of the biggest problems cactus and succulents face and it's better to be on the dry side than to be on the wet side. Too much water can lead to diminished growth, rotted roots, rotted plants, or death. Too little water will show itself through wilting or shriveled plants. Unfortunately, wilting or shriveling can be signs of too much water. Again, get to know your plants. Dig around the soil when problems crop up.

2. Clay Pots versus Plastic
Plants in clay pots, unless they are lined on the inside with a layer that helps retard moisture loss or are glazed on the outside, will need to be watered more often than plants in plastic pots. As a general rule, plants in plastic pots can go without watering for about two or three days longer than those in similarly sized clay pots. There is no right or wrong when choosing between clay and plastic. It's a matter preference.

3. Fertilizer
Every time a potted plant is watered, a small portion of nutrients ends up getting washed (leached) out the bottom. There are a few commercial cactus specific fertilizers available on the market to help replace nutrients lost through watering. They are lower in nitrogen than most fertilizers, thus taking out some of the risk of fertilizing with too much nitrogen. Most fertilizers will suffice in helping to replenish lost nutrients and tend to be a cheaper option than a fertilizer specifically made for cactus. As a general rule, use about half the recommended dose of fertilizer half the recommended frequency. Lastly, only fertilize in the warmer months when plants are actively growing.

4. Sunlight
Sunlight is necessary for healthy plant growth. For a beginner, try to give plants morning and/or late afternoon sun for about three to four hours. Through observation, a grower may find that a plant has to be moved to a sunnier location or that it needs more shade. Plants that aren't getting enough light may have new growth that is a lighter shade of the color of the plant and is thinner and elongated compared to the rest of the plant. Plants getting too much sun will start to turn red or yellow on the fringes and may not grow all that much. Be aware though that a plant turning yellow and/or not growing may be an indicator of too much water in the soil.

5. "Pumped Up" and "Grown Hard"
If you get into the hobby of growing cactus and succulents and get beyond buying your plants from the local hardware store or nursery, you may hear the terms, "pumped up" and "grown hard". Here is an explanation of each.

"Pumped up" is a term applied to plants that are being pushed to the limits of their growth with nitrogen for purposes of getting them sold. They tend to be vibrant plants, could be flowering quite a bit, and tend outshine other plants of the same kind. However, there are problems that could arise from buying such plants. They could have a shorter life, may have more bug problems, since the skin of the plant tends to thinner, and may be more prone to rot, sunburn, and splitting. Plants like this are hard to spot and the best advice is to know what a plant looks like before you buy it. If it's an impulse buy, you're kind of on your own about what kind of care it received before you bought it, for no grower will ever admit they pump their plants up.

I've been growing plants for a long time and thankfully over fertilized plants aren't a widespread problem, but a couple of plants caught my eye at a cactus show recently where I had to go over and see what they were. They stood about seven inches tall, were fat like a Golden Barrel Cactus, and spines kind of on the short side. I had never seen plants like these two before. As it turned out, they were both labeled "saguaro" and they weren't like any saguaros I'd EVER seen before. Both plants sold within the first few hours of the show and that's a shame. Plants like that were clearly growing unnaturally and what will probably happen is that they'll die or look horrible and the buyer will end up blaming themselves.

"Grown hard" is a term applied to plants that are cultivated in such a manner that mimics their natural environment. This usually means that they are slow growing, receive only enough fertilizer to replenish what washes out the bottom of the pot, and have a thicker skin. Plants grown in this manner aren't always the showiest, but they will likely last a long time if given the same care. You're far more likely to be rewarded by a hard grown plant in your care than trying to assess what you did wrong with a pumped up plant. Whereas no grower will tell you that they pump up their plants, all growers who grow them hard will let you know. They take pride in it.