While skimming a magazine from England called Permaculture, I found an article about mounding. The article described how to build mounds in your garden and what materials to use. Over time, the soil becomes richer from the decaying materials. Also, the sides of the mounds provide more space to plant. I realized that I have already done this in my own garden.

When I removed my back lawn many years ago and replaced it with mounds, i used the dried turf from the lawn. I turned the sod upside down for the base of each bed, then proceeded to build the beds up with mulch from my own yard; branches, bark and trimmings. On top of the whole thing I added compost and some garden soil. 

These beds were created 20 years ago and are still looking good. I have some major plantings on them, such as small maple trees and lily of the Nile (Agapanthus). Annually, I add compost and dried leaves to enrich the soil.

I also created a mound when I gave up on my huge walnut tree. The squirrels were stripping it and dropping unripe walnuts everywhere, including into my fish pond. After much consideration i had the tree removed.  

After the stump was out I started to fill the depression with organic materials from my yard. The first layer was sticks and stumps from small prunings around the yard. Then I added leaves and other garden waste and piled soil on top of the whole thing. Since I planted figs on this area, I call it Fig Hill. It also gets annual composting and other soil added to keep the height. 

The sticks and other organic materials that I put in these mounds act like a sponge, absorbing water and holding it for the plants. If you have soil that does not drain well or is hard to work, mounds will help with both of these problems.

With both of these experiences, the results repaid the work. Now is a good time to start such a project in your own yard as you prune and clean up in your garden.

As I learned from the magazine article, one approach is to dig long trenches and then fill them with logs, branches, leaves, grass clippings, straw, cardboard, black and white newspaper, cured manure, compost or other available materials. Then you top it all with good soil. Water well and let the soil and materials start to decompose and settle. Then you are ready to plant vegetables or flowers in your mounds.

The organic content of the mounds gives off heat as it decays and keeps the soil warmer. And the decomposing wood gives off nutrients for years. Hard woods will take longer to decay than soft woods.

An added benefit of the mound method is that it doesn't require tilling. No-till gardens are better for the creatures that live in the soil, like earthworms, so, ultimately, they are better for soil health.

Mound gardens also mean less bending for the gardener.

The article recommended constructing steep beds to avoid compaction from foot traffic. Steep beds create more surface area in your garden for plants, and the height makes easy harvesting. The greater the mass, the greater the water retention.  

Some of the beds shown in the article had straw on the top and sides to hold the materials in place. Others had wire sides with plants inserted between the wires. One gardener used shipping pallets to hold everything in place with plants planted between the slats.

Next workshop: “Sustainable Vegetable Growing” (Four-Part Series) on Sundays February 23, March 1, March 8 and March 15, from 2 p.m. to 4 p.m., at the University of California Cooperative Extension, 1710 Soscol Avenue, Napa. For more details & online registration go to Online registration (credit card only) or call 707-253-4221.

The UC Master Gardeners of Napa County are volunteers who provide UC research-based information on home gardening and answer your questions. To find out more about upcoming programs or to ask a garden question, visit the Master Gardener website (http://napamg.ucanr.edu) or call (707) 253-4221 between 9 a.m. and noon on Mondays, Wednesdays or Fridays.

By Heather Dooley and Pat Hitchcock, UC Master Gardeners of Napa County

The recent rain and cool weather have given us plenty of time to pore over all those seed catalogs looking for a new vegetable variety to try or reordering seeds for our favorites. It's time to start planning your summer vegetable garden (although it's not planting time yet).

Fortunately, we live in an area with a Mediterranean climate, characterized by long, dry summers and mild, rainy winters. As a result, we have two cool seasons annually for gardening, one in late summer and early fall and the other in early spring. Our warm season typically starts in late April when the soil is warm enough to plant tomatoes. Now is the time to start planning for that warm season.

You can start your own warm-season vegetables now in pots. Tomatoes, peppers and eggplants are easily started from seed indoors. These vegetables require warmth to germinate so it's a good practice to put seed-starting trays on a heat mat.

All seeds need the correct temperature and moisture to germinate. But after they sprout, light becomes all important. Put baby seedlings in a sunny spot by a window or, if using a grow light, keep the light about 1 inch above the leaves to prevent spindly, weak plants.

If your seedlings do get leggy or aren't dark green, they need more light. Keep soil moist but not soggy and use a half-strength liquid fertilizer once a week. In about six weeks they will be ready to plant outside.

Be sure the area where you intend to plant your seedlings gets enough sun. Six to eight hours is the minimum for most vegetables.

Do you have a plan for irrigation? And have you examined your soil? Is it nice and crumbly, like a piece of chocolate cake? Or is it waterlogged clay? Clay soil holds micronutrients but typically needs to be amended with compost to lighten it, so it has air pockets for the nutrients to cycle.

Have you been adding organic matter to feed the soil microbes? Soil is alive. It has both macroscopic organisms (the ones we can see), such as earthworms, aerating the soil and decomposing organic matter and also microscopic organisms such as bacteria and fungi.

Mycorrhizae are fungi that live in association with the roots of plants. These fungi collect nutrients for the plants in exchange for carbohydrates. It's a wonderful example of life forms helping each other. There's a whole conversation going on underground in healthy soil.

Don't neglect weeds. Most soils have a large amount of weed seed just waiting for the right conditions. Weeds compete with your vegetables for water and nutrients. Controlling them is a constant part of gardening but can be managed by depriving the weeds of water and light. Mulch your beds to exclude light, water only where necessary for your vegetables and disturb the soil as little as possible to avoid bringing up a new crop.

Plant healthy transplants at the right time to encourage growth and to out-compete weeds. Chemical weed controls are not recommended in a vegetable garden and not needed in most situations.

Now that you have a sunny spot with great soil, access to water and no weeds, what do you want to grow? Ask yourself why you are gardening. Is it for flavor, to save money, to harvest organic produce or to have access to unusual produce varieties?

It's tempting to want to grow everything, but properly spaced plants will be healthier and more productive than plants spaced too closely. Make a planting plan on paper. Think about the size of the vegetable when full-grown and how long it will be in the ground. An indeterminate tomato plant will eventually need almost nine square feet of growing ground and will need to be supported with a strong five-foot-tall cage. Can you stagger plantings for a longer harvest season?

It is better to grow fewer plants well than to have a large vegetable garden that you can't take care of. Gardening is work and therapy, and you get tomatoes, too.

See complete list of upcoming events on our website calendar http://napamg.ucanr.edu 

Free Talk, 1 hour: “Growing Summer Vegetables” at the Napa Public Library on Thursday, March 7, from 7 p.m. to 8 p.m. Learn what you can grow in the summer, what to plant and when, and how to have a harvest all summer long. No registration required.

Workshop, 2 hours: “Growing Spring and Summer Vegetables” on Saturday, March 9, from 9:30 a.m. to 11:30 a.m., at the University of California Cooperative Extension, 1710 Soscol Avenue, Napa. Do you want nutritious, easy-to grow and utterly fresh food from your garden this spring and summer? Learn what the garden needs to successfully produce spring and summer vegetables from seeds and plant starts. In addition to growing basics and hands-on activities, this program includes watering, fertilizing and harvesting tips, with a dash of Integrated Pest Management for pest and disease control. The delight of growing your own groceries is matched only by savoring them at harvest. Online registration (credit card only); Mail-in/Walk-in registration (check only or drop off cash payment).

Workshop, 2 hours: “Summer Vegetables” on Sunday, March 10, from 1 p.m. to 3 p.m., at Yountville Community Center, 6516 Washington Street, Yountville. Get tips for growing your own summer vegetables. Learn some basics, get keys to success, and do hands-on activities to learn about new varieties and review old favorites. Enjoy healthy vegetables taken straight from your garden to your table. The delight of growing your own vegetables is matched by savoring them at harvest. Online registration or telephone the Parks & Recreation Department at 707-944-8712.

Demonstration garden update: UC Master Gardeners of Napa County have begun the process of re-establishing a demonstration garden in Napa Valley. For further developments, please visit the Demonstration Garden link on our website ( http://napamg.ucanr.edu/).

Master Gardeners are volunteers who help the University of California reach the home gardening public with research based gardening information. U. C. Master Gardeners of Napa County (http:/napamg.ucanr.edu) are available to answer gardening questions in person or by phone, Monday, Wednesday and Friday, 9 a.m. to Noon, at the U. C. Cooperative Extension office, 1710 Soscol Avenue, Suite 4, Napa, 707-253-4143, or from outside City of Napa toll-free at 877-279-3065. Or e-mail your garden questions by following the guidelines on our web site, Click on Have Garden Questions? Find us on Facebook under UC Master Gardeners of Napa County.

By David Layland, U. C. Master Gardener of Napa County

It's that time of year: time to start thinking about planting this year's vegetable garden. It's still too early to actually plant seeds or starts but it's not too early to do a little planning.

By now the remnants of last year's garden should be decaying in your compost pile. If not, removing any plant debris from last year should be your starting point. You want a clean slate in case any of last year's plants were diseased.

Once you have cleaned up your garden beds, it's time to add compost. Ideally, you did so last fall, but if you're like me, it didn't happen. Add a good three to four inches of compost so that plants have an ample supply of organic matter to feast on all season. Such a healthy addition of compost will reduce or even eliminate the need for fertilizer.

The time-honored method is to dig in the compost, but many people are now advocating a no-till approach. Digging breaks and disrupts the long, delicate filaments of mycorrhizal fungi that live on plant roots. If undisturbed, these fungi grow downward, branching out like a second set of roots and giving plants access to nutrients deep in the earth.

If the soil is tilled, this network of fungi will need to re-establish itself. When seeds or starts are planted without tilling, they can often hook up with last year's mycorrhizae almost immediately, which gives them an early advantage.

However, soils with poor structure do need to have organic matter thoroughly incorporated into them. If your soil has too much sand or clay, if it is compacted, or if it lacks organic matter, then by all means dig.

Before deciding what to plant and where, take a trip back in time. If you are like me, you have maintained a garden journal to record what you grew in your vegetable garden each year. This information is critical as you don't want to plant vegetables in the same family in the same place every year.

Crop rotation is one of agriculture's oldest cultural practices. In a home vegetable garden, crop rotation involves changing the location of vegetable families each season. Crop rotation reduces damage from insect pests, limits the spread of vegetable diseases and improves soil fertility.

The vegetable families I use in rotation are Solanaceae (potatoes, tomatoes, eggplant, peppers); Cucurbits (cucumber, squash, melons); root crops (carrots and beets); Brassicas (broccoli and cabbage); legumes (beans and peas); and leafy greens (spinach, lettuce, kale). Ideally the same vegetable family should not be planted in the same place for at least three years. I find this difficult as most of my summer garden is devoted to vegetables in the Solanaceae family, so I'm often rotating crops every two years.

Warm weather in March tempts us to start transplanting tomatoes, peppers, squash and other summer vegetables. But it's not the daytime temperature that matters most; it's the soil temperature. Tomatoes want soil warmer than 60°F before they really start growing. Our Napa Valley soils don't usually reach that temperature until mid-April or May.

Peppers and eggplant want even warmer soil. I have planted tomatoes in early April and again in mid-May and found that the plants start ripening at the same time. So you are not really getting a head start on the harvest by planting early.

Most garden centers sell soil thermometers that will give you an accurate reading. However, if you don't want to spend the money on a soil thermometer, try the “sit down test.” Sit in thin shorts on the bare ground. If you can stay seated comfortably for 60 seconds, then go ahead and plant. Otherwise, your tomatoes will just sit there, too, and not grow. I don't believe the University of California has done any research on this method, and since I have a soil thermometer, I haven't actually tried this myself.

You have a few more weeks before planting, so sit back, relax and think about all those fresh vegetables you will be enjoying this summer.

Tomato Plant Sale: U. C. Master Gardeners of Napa County will hold their sixth annual Tomato Plant Sale on Saturday, April 14, from 9 a.m. until sold out, at 1710 Soscol Avenue, Napa. Find more than 4,000 tomato starts in 28 varieties, from popular heirlooms to new hybrids. These Master Gardener-grown seedlings include varieties suitable for eating and cooking, plus cherry tomatoes of many colors, and early, mid- and late-season varieties. A team of tomato experts will be on hand to answer questions.

Master Gardeners are volunteers who help the University of California reach the gardening public with home gardening information. U. C. Master Gardeners of Napa County ( http://ucanr.edu/ucmgnapa/) are available to answer gardening questions in person or by phone, Monday, Wednesday and Friday, 9 a.m. to Noon, at the U. C. Cooperative Extension office, 1710 Soscol Avenue, Suite 4, Napa, 707-253-4143, or from outside City of Napa toll-free at 877-279-3065. Or e-mail your garden questions by following the guidelines on our web site. Click on Napa, then on Have Garden Questions? Find us on Facebook under UC Master Gardeners of Napa County.

By David Layland, U. C. Master Gardener of Napa County

Climate change, also called global warming, has been in the news lately because of the devastating wildfires in Northern and Southern California. Climate change refers to the rise in average surface temperatures and is due primarily to the use of fossil fuels which releases carbon dioxide and other greenhouse gases into the air.

The gases trap heat within the atmosphere, which can have a range of effects on the environment including rising sea levels, severe weather events, and droughts that render landscapes more susceptible to wildfires.

There are two ways to mitigate the environmental damage done by fossil fuels. The most common way is to reduce the use of fossil fuels—by driving a hybrid or electric car, for example, or using solar or wind power. The second way, carbon sequestration, involves pulling carbon out of the air and storing it in the ground.

I don't drive a hybrid or electric car but I do have solar power. It provides 90 percent of my electricity at home so I've done something toward lowering emissions.

Carbon sequestration is new to me. In researching what I could do to help pull carbon out of the air, I discovered that I'm already using several carbon-sequestration practices in my garden. To some extent, these practices are what organic gardeners have been doing for a long time.

Make compost: One of the primary differences between organic and conventional gardening can be boiled down to a simple change in perspective: Instead of worrying about feeding the plants, we should worry first about feeding the soil. Take care of the soil and the plants will take care of themselves.

By composting all of our food scraps and garden waste, we aren't just providing valuable nutrients for plants. We are providing food for a huge ecosystem of bacteria, fungi and insects, all of which help to absorb carbon from the environment and keep it locked up in the soil. You can add cardboard and other paper-based waste to your compost, too. High-fiber composting works, and it's another way to lock up some CO2.

Don't dig: Many old-school gardeners may scoff at the idea of no-dig gardening, but there are good reasons to abandon the rototiller and dig only when necessary. No-dig gardening could have a significant impact on preserving soil carbon.

By slowing down the rate of decomposition in the soil, you help increase soil carbon and save yourself some labor. More than 15 years ago I purchased a rototiller because I thought I “needed” one for my garden and vineyard. I used it for a few years, until I realized I didn't need it. It sat under a tarp for a few more years until I found a new home for it.

That was an expensive lesson. Not using a gas-powered rototiller also means you are not using fossil fuels and are not spewing pollutants into the atmosphere. And you're not killing the hard-working earthworms that are improving your soil health.

When you refrain from tilling, you avoid exposing the soil to excess oxygen and sunlight. You can achieve the same thing by mulching, but an even better way is to plant cover crops, or so-called green manures, which can later be hoed in or mowed down. Doing so will add carbon to the soil while helping the root system keep soil in place. Cover crops also provide a habitat for soil life when you don't have edible crops.

Lose the lawn: This recommendation was easy for me. Before my wife and I moved to Napa, we had a lawn that was more than an acre and, of course, we had a riding lawnmower. After four years of mowing this lawn I never wanted to have another one.

The standard lawn requires a considerable amount of costly maintenance, water and chemicals if you want that green carpet to look perfect. There are many environmentally-friendly alternatives to a lawn. In Napa, I opted for decomposed granite. There's no maintenance and the permeable surface allows water to reach the soil. I added a few drought-tolerant plants for color and trees to shade the house. And I'm saving fossil fuels by not using a gas-powered lawnmower.

Grow lots of stuff (except a lawn): To store the maximum carbon, always keep the soil surface covered with growing things such as trees, turf, vegetables, flowers and cover crops. The more variety, the better. Grow plants with deep, extensive root systems and coarse, woody roots; shallow, fine roots decompose too easily. If I had it to do over again, I might not use as much decomposed granite as I did. At the time, I was focused on lawn alternatives, not on carbon sequestration.

So there you have some tools for carbon sequestration at home. Now go out there and do your part to fight climate change.

Workshop: U. C. Master Gardeners of Napa County will host a workshop on “Rose Pruning” on Saturday, January 13, from 10 a.m. to noon, at University of California Cooperative Extension, 1710 Soscol Avenue, Napa. Why do we prune roses? Is winter the only time to do it? What will happen if we don't? Should hybrid teas be pruned differently from floribundas? Join the Master Gardener Rose Team at this popular forum where resident experts will answer your questions about basic rose pruning fundamentals with research-based information. Topics include rose types, how and when to prune, what tools to use and how to care for them, safety and sanitation.  No doubt each Master Gardener will have some suggestions for new plantings, too. Online registration (credit card only);Mail-in/Walk-in registration(check only or drop off cash payment).

Master Gardeners are volunteers who help the University of California reach the gardening public with home gardening information. U. C. Master Gardeners of Napa County ( http://ucanr.edu/ucmgnapa/) are available to answer gardening questions in person or by phone, Monday, Wednesday and Friday, 9 a.m. to Noon, at the U. C. Cooperative Extension office, 1710 Soscol Avenue, Suite 4, Napa, 707-253-4143, or from outside City of Napa toll-free at 877-279-3065. Or e-mail your garden questions by following the guidelines on our web site. Click on Napa, then on Have Garden Questions? Find us on Facebook under UC Master Gardeners of Napa County.