Mistakes have been made. And I was the one who made them. I bought plants without checking whether they would live through Napa Valley winters.

I bought plants without knowing where I would put them. And I bought plants that needed more water than I was able or willing to give.  

The delicate blossoms on some of my acquisitions couldn’t take our freezing temperatures. Special species languished in their nursery containers, and delicate delphiniums melted in the hot valley sun.  

It is clear that I have more work to do to master the art of gardening. I find that sitting by the fire surrounded by all the lovely new gardening catalogues is the perfect time to make some gardening resolutions.

My first resolution is to study a plant’s requirements before buying it. Most nurseries have a copy of “Sunset’s Western Garden Book,” which I will check for advice on the water, temperature and lighting needs of each plant I’m considering. Catalogues can also be excellent information sources.

I resolve to know my climate zone and consider my garden’s microclimates to ensure that the plants I select will thrive in my garden. I acknowledge that failing to do this puts me at risk of becoming a serial plant killer.

I resolve to dig a proper hole for new plants. The good news is that the old advice — dig a $50 hole for a $5 plant — is now considered outmoded. In our hard clay soils, that kind of digging was a lot of work. In the past, gardeners were admonished to dig a deep, wide planting hole, fill it with loosened amended soil for the roots to grow into, add some fertilizer, and water well.

But that procedure too often results in serious problems. The smooth clay walls of the hole act as a barrier, constricting roots and holding in water. The amended soil settles and the plant sinks, making it a toss-up whether root rot, crown rot or failure to thrive will kill the plant first.   

Today’s preferred way to plant is to dig a hole approximately the same depth as the root ball. Most roots grow out instead of down, so dig a hole that is wider than it is deep. Add amendments if you wish, but do so sparingly. The idea is to encourage the roots to spread out for nourishment and moisture. If the hole is too narrow or too enriched, the roots will just encircle themselves in a tight environment. You can encourage root expansion by roughing up the walls of the planting hole.

I resolve to make my garden truly water wise. Although my water comes from a well and seems cost free, local water issues are pressing. Water is precious in the valley and I want to use it responsibly.  

As a Master Gardener, I have learned that more plants die from overwatering than underwatering. So I have been miserly with water, which is good. But I did not regularly check my plants. Newly planted specimens are especially vulnerable to water stress and, consequently, I lost precious plants. Too much or too little water can kill a new plant in just a few hot days.  

 If a plant loses its sheen, if its colors fade, or if it is drooping, pay attention. It is not getting the right amount of water.  

I resolve to monitor my young plants more closely and, just as importantly, I will set up an automatic watering system to make all my garden water wise. A simple system can be set up off the garden spigot with a battery-operated timer, some tubing and emitters, all found at the local hardware or irrigation store.   

 I resolve to do planting in the spring and fall when the new plants will have an easier time adjusting before extreme temperatures hit.  

And when the planting is done and the emitters are placed, I resolve to mulch, mulch and mulch. A two-inch layer of mulch will keep moisture in, moderate the soil temperature and keep weeds at bay. And I will remember to keep the mulch away from the crown of the plant.

So those are my garden resolutions: Plant the right plant in the right place. Plant it in the proper hole and give it the right amount of water. Monitor plants for stress and cover the surrounding area with mulch. And finally, I resolve to view my garden as a continuing journey, with mistakes to correct and triumphs to celebrate each year.

Master Gardeners  (http://cenapa.ucdavis.edu) answer gardening questions Monday, Wednesday and Friday, 9 a.m. to noon, at 1710 Soscol Ave., Suite 4, Napa, 253-4221, or toll-free at 877-279-3065. Questions may also be e-mailed to the Web site.