Author Archive: Brandon Merchant

Hot & Humid Monsoon Gardening

Red Amaranth

During a recent road trip I was fortunate enough to have the opportunity to visit an American landmark that I had wanted to visit for many years – the Mitchell Corn Palace of Mitchell, South Dakota. The exterior of the Corn Palace is adorned with decorative murals that are constructed almost entirely of corn kernels. It takes over 100 acres of plants to provide enough corn to complete the murals. Each year a new theme is selected for the murals and they are taken down and replaced, this year’s theme was “Remember When.”

It may seem odd to have a palace dedicated to and built from corn, but for a Southwestern gardener like me, a palace dedicated to corn seems very appropriate considering corn’s importance in our region – both historically and today.

Corn has been grown in the Americas for thousands of years as a staple food crop for the Native Americans that domesticated it. Today, when most people think of corn they picture a steaming sweet yellow cob that often accompanies meat and potatoes at summer barbecues. In all actuality this type of sweet corn is a relatively new discovery, botanically speaking. The majority of corn grown both historically and today is used as feed for livestock or as a base ingredient for any number of food and non-food products. It is estimated that it takes 25 corn plants per person per day to maintain the American way of life.

Here in the southwest, tribes such as the Tohono O’odham, Quechan, and Gila perfected varieties of dent, flint, pop and sweet corns that grow exceptionally well when planted along with the heavy monsoon rains that occur this time of year. Tohono O’odham 60 Day, Yuma Yellow and Gila Pima “A:al Hu:n” are just a few of the many varieties of corn that grow well when planted with our summer rains. Other varieties to consider are Golden Bantam 8 Row, Golden Bantam 12-Row and Hopi Blue.

Along with corn, a wide variety of edible crops have been domesticated to grow and thrive in the hot and humid conditions that are characteristic of the monsoon. The main benefit of growing native crops that are indigenous to our area is that they are already acclimated to our extreme weather conditions; however there are several added benefits. First among them is that many of our native crops are highly nutritious. Amaranth, for example, is often touted as the next super food for its high nutrient content. My favorite variety of amaranth is Hopi Red Dye for the color it brings to the summer garden, but you will also have success growing the varieties Mayo Grain and Alamos.

Another benefit of planting a monsoon garden of native crops is that they are often very different than what is commonly available at grocery stores and farmer’s markets. This variety will bring a little excitement to your culinary experiments. Tepary beans are highly nutritious and the most drought tolerant of any bean. Tests have shown that they can subsist without any external irrigation whatsoever. For gardeners in cooler parts of our region, the Bolita bean is a great substitute for the common pinto bean as they taste better, cook faster and have a creamier texture. Other crops to consider for your monsoon vegetable garden include cowpeas, okra and watermelon.

When planning for your monsoon garden keep in mind that although the crops discussed above generally thrive during this hot and humid season, they still need to be planted in such a way that that they are able to take advantage of short bursts of heavy rain. Planting in a sunken bed or basin is the traditional growing method for a monsoon garden. Designing your garden in this way will help to conserve as much rain water as possible. If possible, rain water should be directed from your roof or any other catchment to the garden where it will do the most good. Your garden will also benefit immensely if you incorporate other organic gardening principles such as intensive spacing, companion planting and mulching into your plans.

All of the seed varieties listed above can be found online at NativeSeeds.org or by visiting the Native Seed/SEARCH retail store at 3601 N. Campbell Ave. Brandon Merchant is the proprietor of Southwest Victory Gardens. Visit his website at SouthwestVictoryGardens.com.

Coping with Summer Pests

There is nothing more reminiscent of summer in Southern Arizona than the sound of cicadas buzzing away in the heated stillness. This pleasant humming provides the soundtrack for summers in our region and for those of us who have lived here our entire lives, their return is often a cause for celebration. For vegetable gardeners, the return of the locust is often a bittersweet moment because with it marks the return of a wide variety of insect pests that like to make our summer vegetable gardens home.

Considering that Arizona is home to over 13,000 unique insect species, with many more yet to be discovered, it should come as good news that only a small fraction of these can cause harm to plants in the vegetable garden. Of the three dozen or so that can become a nuisance, only a small percentage require diligence on the part of the gardener to keep them under control. Fortunately, a lot of research has gone into developing control methods for the most destructive backyard garden pests.

Many gardeners shiver at the first appearance of an unknown insect in the garden. Perhaps it’s an innate fear of insects they developed as a child, or perhaps it is effective marketing on the part of poison pushers like pest control companies and pesticide manufacturers. Regardless of the reasoning, the fear is most often a result of a misunderstanding and not grounded in reality. In reality, most insects are harmless and it takes an awful lot of neglect on the part of the gardener to let the damage caused by insects to reach a point that can actually harm garden plants.

Tobacco hornworm, larva of Manduca sexta, on a cherry tomato plant.
photo: Wikimedia Commons

Another reality often overlooked or ignored by gardeners is the fact that the presence of insects, even pest insects, does not necessarily indicate a problem and in fact some of the “damage” caused by these insects can actually be quite beneficial to the plants which are afflicted. Tomato hornworms, for example, perform a great pruning service if not left to take over and can actually encourage new growth of tomato plants. Although they may not do the job exactly as a trained professional would, you can rest assured knowing that your plants will be much better off than the plants down the street that were treated with a toxic pesticide.

The most common response from gardeners when faced with the hornworm or any other leaf chewing caterpillar is to first freak out, and then second to reach for the closest pesticide to deal with the “problem.” Once this cycle is started it is very difficult to get out of. After the adult caterpillars are eliminated, any predatory wasps that may depend on them for breeding will also end up leaving, which in turn can result in the appearance of an even greater number caterpillars in the future. As the cycle progresses, more applications of pesticides are required and the problem is exacerbated.

It may not seem beneficial at first, but there are many positive aspects to the presence of a few pest insects in the garden. As soon as pest insects begin to arrive, it also signals the return of their natural predators. When drastic measures are taken to eliminate the pests, we often unknowingly also eliminate the many predators which naturally keep those pests at bay. These can be insect predators such as the ubiquitous green lacewing or even larger predators such as birds. More often than not, gardeners are too quick to resort tactics that will alter or even eliminate the delicate ecosystem needed to grow a healthy garden.

So what is a gardener to do? No one, including myself, wants to give their garden over to bugs when so much time, work and money have gone into producing a crop. The trick is to approach the situation with a good attitude and to take the least invasive steps possible to eliminate the problem. Although not an instant fix, when basic initial steps are taken we can begin to create a garden environment that is both inhospitable to pest insects and attractive to beneficials.

The first step is to provide your plants with a proper growing environment that meets or exceeds their nutritional requirements. Sickly, malnourished, or drought stricken plants actually attract pest insects while healthy plants actually repel them. Well cared for plants will also bounce back quicker from an attack than those that may be lacking in nutrients. Infestations will rarely occur in a healthy garden. Further steps can be taken to reduce the chance of a pest outbreak. Timing your plantings so that your crops will be well established by the time pests arrive is very effective. A sprawling squash plant will send out roots all along the vine so that if a vine borer severs the main stem the plant will still survive.

Furthermore, by planting cultivars that are already resistant to the most common pests in our region, we can almost eliminate the chance of attack all together. A good example would be butternut and acorn squash, which both are resistant to squash vine borer attack. Further control can be achieved when organic gardening methods are incorporated into your garden plan. The most successful techniques include interplanting of pest repellant plants amongst the garden or even dedicating a small area of the garden to plants that will provide a habitat for beneficial insects.

These methods take time to work and are not instantaneous, but when combined with due diligence on the part of gardener, then the likelihood of your garden being invaded will be greatly reduced. While not as satisfying as emptying a can of Raid, in the long run you and your garden will be much healthier.

Brandon Merchant is the proprietor of Southwest Victory Gardens. Visit his website at SouthwestVictoryGardens.com.

Plant a Square Foot Garden

Those of us who have been gardening in the Southwest for more than a few seasons have probably come to learn that the advice found in most gardening books and magazines just doesn’t work in our climate. One of the first lessons learned comes from following generic planting recommendations printed on seed packets. The planting dates for our area are usually wrong and the recommendations often call for planting in long, mounded rows.

In other parts of the country, where rain and space is plentiful, row planting makes sense. Here in Tucson however, planting this way can lead to thirsty plants.  But even after converting to basin-style gardening, which is more appropriate for our area, many gardeners still continue to plant in row fashion by scattering large amounts of seeds along shallow trenches. Not only is this technique wasteful, but it leads to more work and crowded plants.

An example of square foot gardening at The Garden Kitchen in South Tucson, where Brandon Merchant teaches classes once a month.
photo: Brandon Merchant

Fortunately, there is an alternative to row planting that will not only save you time, but will also allow for increased yields while reducing the need for weeding and the amount of water required to keep your garden healthy. I’m speaking of the square foot gardening method; a system that was developed by civil engineer Mel Bartholomew in the 1980s.

Unlike row planting, square foot gardening involves creating small but densely planted gardens with the goal of maximizing yields from smaller spaces. The technique borrows heavily from earlier sustainable agriculture methods such as French intensive planting and biointensive agriculture, but it is designed for the relatively small backyard vegetable garden.

Any garden space can be converted into a square foot garden by following a few simple steps. First, in order for vegetables to be planted densely using the square foot method, your soil must be heavily amended or even replaced with a nutrient-dense growing medium. The most common medium is a mixture of compost, coco coir and vermiculite. This mixture of ingredients provides the perfect balance of nutrients, water holding capacity and soil aeration that densely planted gardens thrive in.

The ratio at which these ingredients are mixed can be adjusted to fit your garden and your budget. In the bestselling book Square Foot Gardening, Mel Bartholomew recommends an even mix of 33% of each ingredient; however these are only recommendations and need not be followed to a T.

Although the soil mix is very important, what ultimately defines a square foot garden is the layout. Prior to planting, the garden is first divided into one foot by one foot squares. You can do this easily by using garden twine and tent stakes, or if you’re feeling industrious you can make a more permanent grid using lumber.

Within each square of the grid, crops are planted in a pre-defined pattern. For example, in one square foot you could either plant nine turnips, 16 carrots or one eggplant. Every square foot has a maximum number of each crop that can be planted in it. Although it is not necessary to plant the recommended maximum number of plants, you should never exceed the recommendation. When planting from seed, great care should be taken to not over plant; two or three seeds per hole are usually sufficient. What may seem like a meticulous task at first will save you time in the long run.

Square foot gardening can also be combined with organic gardening techniques such as succession planting, intercropping, cover cropping, and companion planting.  Crops with similar square foot growing requirements can be combined for more effectiveness. For example, one square foot could hold a mixed combination of 16 radish and carrots.

There are many square foot garden planting guides available online for free or you can learn more by picking up a copy of Square Foot Gardening at your local book store or library. Another great way to learn how to properly plan your square foot garden is to subscribe to an online garden planner service such as GrowVeg.com or the Mother Earth News online garden planner. Each of these programs offers a free 30 day trial and both allow users to create their own unique garden plans using the square foot gardening method.

Brandon Merchant is the proprietor of Southwest Victory Gardens. Visit his website at SouthwestVictoryGardens.com.

It’s Tomato Time Tucson!

Smaller tomatoes do very well in Tucson.
photo: Jamie Manser

March brings with it warmer weather and a new planting season in the Old Pueblo. Some of our fellow gardeners have taken advantage of the unseasonably warm temperatures in February to get a head start on their spring crops. Others, like myself, all too weary of a late spring frost have resisted this temptation. Regardless of your risk tolerance, late February through March is the prime time to plant tomatoes.

Tomatoes are the bane of desert gardeners everywhere because all to often plants end up looking green and lush with little to no fruit to make the investment worth it. In my conversations with gardeners, I’ve learned that the majority of the time this outcome could have been avoided had a few initial steps been taken. By following these simple guidelines, your likelihood of producing a bumper crop in 2014 will be greater than ever.

Success with tomatoes all starts at the nursery or with the seed selection. Forget the monster Mortgage Lifter that may have won you the blue ribbon at the county fair back home. Large beefsteak type tomatoes do not grow well in our climate and will most likely split before they reach their full size. Conversely, smaller tomatoes do very well. Local seed source Native Seeds/SEARCH has many great heirloom varieties of cherry type and small tomatoes, including Flamenco, Punta Banda and Texas Wild Cherry.

There are some other important factors that you should consider when selecting tomatoes varieties to plant in the low desert. Tomato cultivars with shorter days to maturity or those have been bred for heat tolerance are also known to do well in our climate. Some good examples you’re likely to find include Yellow Pear, Cherokee Purple, Stupice and Pearson Improved. After you have chosen a suitable variety of the low desert, the next step is make sure you get your tomatoes planted at the right time.

The most common mistake Tucson gardeners make is waiting too long to plant their tomatoes in the ground. As a result, they get poor yields. Tomato seeds should be started indoors or in the green house starting in December and transplants should be planted outdoors starting in mid- to late-February and continuing through mid-March. If you wait much longer than this to get your tomatoes in the ground, your yield is likely to drop as hot temperatures set in—decreasing fruit production.

Unlike most garden transplants, tomatoes are planted in a trench rather than a hole.  Trim your new tomato starts leaving only the top two sets of leaves. Dig a small trench one inch deep and the length of a stem with a hole on one side just large enough to accommodate the root ball of the transplant. Gently lay your new seedling in the trench and cover the entire stem leaving only the top two leaves exposed.  Your plant will grow slowly over the next few weeks, but by planting this way a strong root system will develop rewarding you will better drought tolerance and more fruit production in the spring.

Because tomatoes are tropical plants that prefer warm temperatures planting them in the ground late in the winter can present some challenges.  You must be prepared to care for your tender young seedlings if nightly temps drop to freezing levels. Small plants can be covered at night using a cloche made from home made materials such as an old milk jug or a 3 liter soda bottle. You can read more about how to protect your garden from frosty weather in the November issue of Zócalo Magazine.

As the season progresses and your plants continue to grow, you’ll want to care for them by applying organic fertilizers on a regular basis throughout the season. My favorite is Tank’s Green Stuff compost. Mix in generous helpings of compost to the soil at the beginning of the season before planting, and apply a two inch layer of compost mulch as the weather warms in April. Nutrients will be slowly released into the soil each time you water and the mulch will help to reduce watering needs during the summer. Tank’s compost, as well as tomato seedlings of some of the varieties discussed above can be purchased at Ecogro or Green Things Nursery.

Brandon Merchant is the proprietor of Southwest Victory Gardens. Visit his website at SouthwestVictoryGardens.com.

Frost Protection for Southwest Gardens

Frosted vegetation on a winter morning.
photo: Jamie Manser

One of the best reasons to be a gardener in Tucson is the fact that, in Southern Arizona, we can have a garden growing all year long. Unlike other parts of the country where the ground freezes solid in the winter, Tucson winters are mild enough to grow a wide variety of cool season vegetable crops such as broccoli, lettuce and spinach.  However, just because these crops don’t mind the cool temperatures doesn’t mean that we don’t need to give them some protection from time to time.

Mid- to late November, and through December and January, are usually the times of year we can expect to experience our frost temperatures. Light frost occurs between 32-28 degrees. Most winter vegetable crops can handle short exposure to these temps with little to no damage; however it is at these temps where summer vegetables will die off. A hard frost occurs as temperatures dip below 28 degrees. The longer it stays below hard frost temperatures, and the lower they get, the more likely your winter vegetable garden will experience frost damage.

Other weather factors such as wind, humidity and cloud cover also play an important role in how frost affects your vegetable garden. Clear, calm nights with little or no cloud cover will let warm air escape back into the atmosphere increasing the chances of frost damage. Moisture in the atmosphere holds heat which can protect your plants, while wind can help keep cool air from sinking to ground levels where your plants reside.

If frost is in the forecast, you can take some basic steps that will help increase the chances your plants will make it through the night. First, a two inch layer of alfalfa hay mulch should be applied to any vegetable garden. Not only does the mulch act as a slow release fertilizer and provide a living environment for soil microbes, but the mulch also acts as a great insulator that keeps plant roots warm on chilly nights. Intensive spacing of vegetable crops will also aid in protecting plants from frost damage.

A good next step is to water your garden the morning before you’re expecting a frost. The water in the soil will act as an insulator absorbing the sun’s heat during the day and radiating it back at night. You can also protect your vegetables with water by lightly misting them. Misting your plants works to protect them by creating an igloo like effect that keeps temperatures above hard frost levels.

You can help warm air stay close to plants by covering them at night with a sheet or frost cloth, but be sure to never use plastic. Frost cloth or frost blankets are a light material designed to keep warm air trapped against the ground where plants are growing. Frost cloth is nicer than sheets because it allows sunlight to reach the plants so they can be left on during very cold days whereas sheets need to be removed in the morning. It can also be doubled up to increase protection.

Garden centers and hardware stores will often sell out of frost cloth when a freeze warning arrives, but Tucson Organic Gardeners usually keeps a good supply on hand. For frost cloth to work most effectively, it needs to cover the plants
completely to the ground without touching them. You may need to construct a frame around your garden using PVC or wire fencing to keep the frost cloth from touching the tops of plants.

Another effective tool for your frost protection arsenal is a strand of old Christmas lights. Christmas lights radiate heat and can act as mini heaters in your garden. Simply place strands around the garden on frosty nights.

For the most part, we only need to take these precautions a few times a year, but it is nice to be prepared for the worst. Frosts can be frustrating but they actually have benefits; they limit the numbers of pest insects, kill off non-native invasive plant species, and also increase the flavor of many winter vegetable crops. So don’t be discouraged if a frost is in the forecast, just be prepared.

Brandon Merchant is the proprietor of Southwest Victory Gardens. Visit his website at SouthwestVictoryGardens.com.