Seasonal Gardening « Southwest Gardener Newsletter

It’s Time To Feed Citrus

citrus Established citrus plants need to be fed three times a year and February is the first time in the year to fertilize. May and September are the other two months. Here’s an easy way to remember: Valentine’s Day, Mother’s Day and Labor Day (all good holidays!).

It is best to use a fertilizer formulated especially for citrus or generally for fruit and nut trees. All citrus trees will benefit from a heavy nitrogen fertilizer that has some phosphorous in it. Citrus trees also like to have somewhat acidic soil, so look for that in a fertilizer, too.

We like the Marine Cuisine 10-7-7 time-release fertilizer from Fox Farm. It is a high-nitrogen blend of plant foods and crab meal, shrimp meal and bat guano in an ideal mix that promotes healthy growth and long-term nutrition. It also revitalizes depleted soil. Amy has been using it on her Lisbon lemon tree for years and is happy to report the tree thrives and produces lots of tasty fruit.

Read the instructions on the bag to determine how much fertilizer to use, depending on the size of your tree. Typically it’s the amount you can hold in a closed hand for a small tree, up to 2 cups for a large tree.

Here’s a handy chart detailing Arizona citrus fertilizer requirements from the University of Arizona Cooperative Extension.

You can take the same total amount of fertilizer recommended for three applications and split it up into nine applications for every month from February to October. Nine light regular applications promotes better tree growth, especially for young trees.

But please don’t fertilize after October. You don’t want to promote new growth when there is danger of frost.

The Scoop on Soil & Amendments

You know macronutrients from the back of fertilizer packages: nitrogen, phosphorus, and potassium are the N, P, K (respectively) letters on the package. Then there’s calcium, magnesium and sulfur. These six get used up very quickly in soil – especially Southwest desert soil – and need to be replaced regularly. Micronutrients are key to plant growth and are needed in smaller doses. They include iron, zinc, boron, chlorine, copper, molybdenum and manganese. A good balance of all these elements will ensure a successful garden, just make sure you use them regularly. A single use will get your great looking plants – for about two weeks.

So here are the details on our favorite FoxFarm products:

FoxFarm Original Planting mix – This stuff is great. A premium organic planting mix to work into the soil every time you plant. It’s got everything to get your garden off to a good start: earthworm castings, bat guano, Norwegian kelp meal, composted forest humus, sphagnum peat moss, and more. This special mix also helps hold moisture in the soil, which keeps plants hydrated and growing. We like this for starting seeds, too.

Ocean Forest Soil – Perfect right out of the bag. Ph adjusted for optimum fertilizer uptake, but you won’t need it for a few weeks because this bag of soil is packed with earthworm castings, bat guano, fish and crab meal.

Happy Frog Potting Soil – Great for pots and container gardens. Whether you’re growing a ficus in the dining room, a geranium on the patio, or a lemon tree on the deck, use this soil full strength in containers.

Happy Frog Soil Conditioner – The FoxFarm folks like to say “Don’t treat your soil like dirt.” That’s because they blend pH-balanced forest humus, earthworm castings, and bat guano, microbes that stimulate root development and humic acid to help increase the uptake of micronutrients. FoxFarm recommends refreshing roses by working a 3-inch layer of soil conditioner into the base of plants twice a year. It’s also great on a lawn and a perfect compost-like addition to raised beds.

Big Bloom Liquid Plant Food (0.01-0.3-0.7) – We love this gentle odorless, liquid fertilizer that’s full of vitamins, amino acids, natural growth hormones, enzymes, and beneficial organic microbes. You’ll get a balanced range of nutrients from Big Bloom. Big Bloom is good for all flowering and fruiting plants, and it’s safe enough to use every time you water. If you’ve got a struggling plant, FoxFarm suggests a root drench of Big Bloom will bring it back to life.

Marine Cuisine (10-7-7) – The benefits of ocean materials are well-known to growers and Marine Cuisine packs lots of seafood into an all-purpose fertilizer. Crab meal, shrimp meal, seabird guano, and kelp, with low-sodium mineral plant foods will offer plants a quick boost as well as time-released nutrition. Amy throws it under her Lisbon lemon tree a few times a year and is never disappointed.

Peace of Mind® Tomato & Vegetable Organic Fertilizer (7-4-5) – Feeding plants is crucial to garden success in the desert, and this Tomato & Vegetable Organic fertilizer is popular with our veggie growing customers. It’s the perfect food for your food.

Sledgehammer – This is a new FoxFarm product designed to remove excess fertilizer buildup (mostly concentrated mineral salts) from around your plants. That’s a big problem in our desert soil. Sledgehammer is great in established gardens, containers and even hydroponics. Best of all you don’t have to interrupt your plant feeding schedules to use this rinse.

A note about nitrogen: Be careful with high nitrogen fertilizers. They really only belong on lawns and will burn and or kill most everything else. Lawns need high nitrogen (N) for their green color, a bit of phosphorous (P) for root development and even less potassium (K) for general health.

Frost Update & January Planting

Frost damage in central Phoenix.

We’re hearing reports of a bit of frost damage in the past two weeks. Calm, clear nights bring the most chance of frost because there are no clouds to trap heat and there is no wind to mix the rising warm air from the soil with descending cold air.

If any of your plants have suffered frost damage there are two really important things to remember when managing the plant:

1) The last average frost date ranges from Feb. 7 in the central part of Maricopa County to April 3 in the far east Valley. (That’s hard to believe but remember we’re dealing in averages.)

Wait for new growth to appear before pruning.

2) Do not prune any frost damage from plants until new growth emerges in the spring. Frost damage is ugly, but it will help insulate the plant if there is another freeze, plus you could do some major damage. Often new growth comes out of that dead-looking tissue.

Going forward, you’ll need to keep plants well watered. Frost injury occurs when ice crystals form on the leaf surface drawing moisture from the leaf tissue. The damage from this dehydration will be less severe if the plant is not already drought-stressed. So, you’ll want to keep everything evenly moist, not letting things dry out too much.

If it looks like temperatures will dip below freezing, cover your plants with sheets, blankets or towels. It’s best to hang the frost covering over stakes placed around a plant, not lay it directly on the leaves. If possible, let the covering hang to the ground to trap heat, but don’t tie it to the trunk of the plant because you want to get as much heat off the ground and close to the plant as possible.

What To Seed In January

According to our well-worn copy of “Desert Gardening for Beginners” January is a good time to seed beets, carrots, green onions, mustard greens and radishes. You can still also seed lettuces, chard and spinach, but they will bolt if we get an early spell of heat. The beets, carrots, etc will continue to produce well into a warm spring.

Winter Garden Care

This can be a tricky time to garden. One day it will be warm and sunny and the next can be cold and blustery. Here are a few tips for keeping your garden in top condition.

Be prepared for frost: Frost can hit the Phoenix area as early as mid-November, and you don’t want your plants to be damaged. You can use burlap, old sheets or a product called N-Sulate to cover your plants in the early evening. Please don’t use plastic because it will burn plant material that it touches. Drape the cloth over the plat so that it touches the ground. Remember to take off the covering in the morning.

Lawn care: Winter rye grass lawns need monthly fertilizing this time of year. Amendments that are high in nitrogen are best. Please remember that your winter lawn does not need daily watering, once it is established. In fact, over watering will cause a host of problems. There is a great grass watering guide in “Landscape Watering by the Numbers,” a FREE publication published by the Arizona Municipal Water Users Association. Come by the shop, we have stacks of them to give away. Again, they are free and will save you water and money.

If you don’t have a winter lawn, remember that dormant Bermuda lawns will still need monthly watering if we don’t get good winter rains.

Remember to Fertilize - Your fall/winter veggies will continue to grow, but you should be applying a mild fertilizer to them about every two to three weeks for maximum growth and production. We like Big Bloom or the Tomato & Vegetable fertilizer from Fox Farm.

Plant Wildflowers: You’ve still got time to scatter wildflower seeds for a beautiful spring show. Try Mexican Poppies, Firewheel, Desert Bluebells, Owl’s Clover, Parry’s Penstemon or any of the mixes we have in stock from Wild Seed. Keep soil/seeds moist until germination and then water once every two weeks if our winter rains don’t arrive.

Plant Citrus: You can plant new citrus trees now. Just remember to protect them from frost.

You can still plant seeds

Herbs and vegetables – Beets, Carrots, Corn, Cucumbers, Jicama, Melons, Okra, Radishes, Summer Squash, Basil, Catnip, Chamomille, Chives, Fennel, Feverfew, Tarragon, Lemon Balm, Lemon Grass, Marjoram, Mint, Oregano, Parsley, Sage, Savory, Scented Geraniums, Thyme, Yarrow.

Flowers – Bee Balm, Butterfly Weed, Black-eyed Susan, Celosia, Coleus (an excellent plant for shade), Cosmos, Desert Marigold, Four O’Clock, Gallardia, Globe Amaranth, Hollyhock, Impatiens, Marigolds, Mexican Sunflower, Portulaca, Sunflowers, Sweet Alyssum, Yarrow.

Here’s what to plant in the low desert in August and September

Yes, it’s hot and cooler temperatures are probably a good month away, but this is the start of the fall gardening season in the low deser. It’s also our best gardening season and you won’t want to miss out. There are many seeds and transplants that should go into a bed now so you get a bountiful crop as fall and winter arrive.

Remember, soil prep is crucial to the success of any garden. Here are a few quick, but very important tips:

* Break up your soil to a depth of at least 12 inches – 18 inches is even better. Do not work wet soil. Moist is OK to turn, not wet.

* Work organic matter – compost - into at least 10 inches of your soil. This loosens it and adds nutrients. If you use manure, use manure that’s from plant-eating animals and that is aged at least six months.

* You can also add fertilizers now, if you wish. Sulfer is good, gypsum helps to break up heavy soil. Turn them deeply into the soil.

* Water the area at least two feet deep.

* Let the soil rest about two weeks and then get busy planting.

Here are vegetable seeds you can plant, according to the Maricopa County Cooperative Extension planting guides:

Snap beans, bok choy, broccoli (in all its variations), Brussels sprouts, cabbages, carrots, collards, corn, cucumbers, kale, kohlrabi, lettuces (head and leaf), leeks, mustard greens, onions, pumpkins,and squash (summer and winter).

Yes, go ahead and plants tomatoes as long as they are transplants. It’s a bit early for herbs and flowers. We’ll let you know when they can go in.

Summer Yard & Garden Checklist

It’s been a terrific spring. Even now, it’s still not searing. Woo hoo! But it’s important to remember that as we head into June we’ll face our driest month of the year. This is the toughest time of the year for plants. Here’s how to get your plants through the heat:

Zinnias make great cutting flowers.

But, first. You can still plant – Cucumbers, Melon, Okra, Sweet Potatoes, and for some glorious color, Zinnias. They love the heat.

Mulch, mulch, mulch - This helps minimize water evaporation from the soil and lowers soil temperatures. Good mulch will also help to create a barrier for weeds.

Keep weeds at bay - Nut grass and spurge are particularly prevalent this time of year – they love to follow the water. Make time in the early morning to pull the weeds. You’ll keep your plants from being choked off and you’ll save yourself a bunch of time come fall.

Water well - Lawns will need approximately 1 inch of water per week during the hottest part of the summer, but how much water is 1 inch? A rain gauge or even an empty tin can set out while your sprinkler is running is a great way to check. Early morning is the best time to water. Studies have shown that when you water during the hottest part of the day almost 50% of the water evaporates before it reaches the ground.

Check watering depth – Trees should be watered deeply about once every 10 days. For most trees, water from your lawn’s sprinkler system is not enough to prevent heat stress. A good soak with a hose at the perimeter of the tree canopy works best. If you’re not sure how far into the soil the water goes, push a metal stake into your wet ground a day after watering to check how deeply it has saturated. Deeper is better.

Control Pests – Heat stressed plants are a prime target for bugs. We get lots of calls this time of year about the best way to keep bugs at bay – on indoor plants as well as the ones outside – in a safe, non-toxic way. We like the organic insecticidal soaps from Pharm Solutions that help keep bugs and fungus from attacking houseplants, vegetables, herbs and flowers. Pharm Solutions are made from certified organic essential oils and soaps. These formulas are so good they were chosen by the National Lawn and Garden Manufacturers Distributors Association as best new product for 2005.

Mind your mower – Practice the “the 1/3 rule” when you mow by not cutting more than 1/3 of the length of the grass. Studies have shown that yards that are cropped too close actually grow quicker than their taller counterparts. A good height for Bermuda grass is 1 ½”. Cut it when it reaches 2 ¼”.

Prune before monsoons – Get out early in the morning and prune your desert trees to prepare them for monsoon winds. They have finished leafing out and the heat seems to heal the pruning wounds faster. Be sure and check for crossing limbs and limbs that have become intertwined. You’ll want to avoid a tangle of catching the wind during storms, creating the perfect opportunity for tree damage and breakage. Felco Pruners and Saws are the best pruning tools available. We use them with good results, plus they are available in right- or left-handed styles. If you hire someone to trim your trees make sure that you select a certified arborist. Chances are the guy that knocks on your door with a chainsaw doesn’t have the training needed to make sure your tree looks and grows to its fullest potential. If you need a tree trimming referral, call us at 602.279.9510.

Tomato Planting Tips

Here’s a quick primer on planting tomato starts.

1. Water your tomato plants a few hours before planting. You want the root ball to be moist, not dry.

2. With your fingers, gently pinch off the bottom leaves of each plant, leaving two to three sets of leaves.

3. Dig a hole with a hand trowel in your amended soil that is deep enough to allow the bare potion of the plant stem to be buried right up to the leaves left on the plant.

4. Place the plant in the hole and fill the space with soil up to the bottom of the remaining leaves on the plant. Do not bury the leaves that remain on the stem of the plant. Gently firm the soil around the plant with your hands.

Note: Only tomatoes are planted this way. It allows the plant to sprout roots along the buried portion of the stem, making the plant stronger.

5. Water the transplant well and a few hours later water again with a half-strength dose of gentle fertilizer. We like Big Bloom from Foxfarm. It’s organic, it’s not too strong and it works. Do not water again until the soil is between damp and dry. One of the worst things you can do is overwater.

6. Tomato plants are quick growers, so keep stakes or cages handy to support them as they grow.

7. Fertilize once a month for in-ground tomatoes, every three weeks for tomatoes in containers.

And remember, never apply fertilizer to plants with dry soil or that are water stressed. Always water the plant first or you’ll fry it with the fertilizer.

Rose Pruning

It’s rose pruning time and we’ve found these helpful tips courtesy of the U of A Cooperative Extension and the Clemson Cooperative Extension publication, “Pruning Roses” by Karen Russ and Bob Polomski.

Pruning roses keeps the plants healthy, promotes new growth, removes dead, broken or diseased canes, and/or trains the plant to a desired shape. It’s important to prune because it encourages flowering, either more blooms or larger blooms, and keeps modern rose varieties blooming repeatedly all summer long – even in our hot desert.

Roses need different types and timing of pruning depending on their variety. Repeat blooming roses such as floribunda and hybrid tea roses need a heavy annual pruning that is done in late January in the desert, early spring in colder climates, just as the buds break dormancy. The best way to judge when to prune is to look at the buds; when they begin to swell, start pruning. Old-fashioned roses and climbers that bloom only once a year should be pruned immediately after flowering. Do not prune these types of roses heavily in the early spring since they bloom on wood from the previous year’s growth. Dead, diseased or damaged wood on any rose should be removed as soon as it is seen.

To prune you will need: sharp bypass hand pruners, loppers, and possibly a pruning saw for larger cuts. When pruning, keep the hand pruners and loppers in a coffee can filled with 70% isopropyl alcohol to minimize disease transmission. Sturdy gloves with long cuffs and a long-sleeved shirt will protect your hands and arms.

The main steps in pruning roses is the same for all rose types.
1. Remove all dead, damaged or weak stems leaving only the most vigorous, healthy canes.
2. Check to make sure the stems show no sign of discoloration. The center of the canes (rose stems) should be white and plump, not brown and withered. If they appear diseased, you will need to cut farther down into healthy wood. If no live buds remain, remove the entire cane.
3. Prune the bush to make it more open in the center. This will increase air circulation and help prevent diseases. Since rose bushes send out new growth from the bud just below a pruning cut, try to make pruning cuts above a leaf bud facing out from the center of the plant.
4. Make a cut 1/4 inch above the bud and angled at the same angle as the bud. Whenever two canes cross each other, one can be removed.

Deadheading is cutting off spent flowers. Old blooms left on the plant may begin to form hips (rose fruit). Hips are often very attractive and can be left on some roses for winter interest and bird food. Hybrid tea roses and other roses that can rebloom should not be allowed to form hips, so that the plant will put its energy into flowering. To deadhead, remove the flower by making a diagonal cut just above the next five or seven-leaf branch down on the stem. This should be above a strong bud that will produce a healthy cane. All pruning cuts on canes greater than the thickness of a pencil can be sealed with wood glue to prevent cane borers from entering.

Hybrid Teas, Floribundas and Grandifloras
Prune hard if you want large blooms suitable for cut flowers. This will produce fewer total blooms. Cut out all but three to five of the healthiest, most vigorous canes. Prune these canes down to 15 to 18 inches from ground level. Keep any weak, small or short stems pruned away. Generally with hybrid teas, any cane thinner than a pencil should be removed. In the late fall, prune roses back by about one-third of their height.

Climbing Roses
Old-fashioned rambling roses and one-time spring-blooming climbers produce best shoots growing off one-year-old wood, and they should not be pruned until after they flower. Cut away all weak or damaged stems and remove the oldest canes, leaving five to seven strong canes untouched. Remember that flowers are produced on stems at least one year old on most running or climbing roses. The stems that you leave will bear next year’s flowers. Climbers that bloom on the current season’s growth can be pruned more severely.

Old Garden Roses
Old roses do not need the hard pruning that is needed by many modern roses. Hard pruning can ruin their graceful shape and severely reduce their flowering. Preserve the informal habit of old garden roses by removing no more than one-third of each bush. Generally, remove only the oldest stems that are no longer productive. Most old garden roses bloom once in a season. Prune immediately after bloom to keep old roses under control and vigorous. Leave some of the bright red hips for fall and winter color.

Miniature Roses
Ever-blooming varieties can be lightly trimmed or tip-pruned several times a year, as they flower on new growth.

Ready, Set Grow!

Cooler temperatures and shorter days are on the way, so this is an ideal time get out and enjoy your yard and garden. We are packed to the rafters with 2009 seeds, tools, gadgets and fertilizers to make this – our best planting season – a snap. Here is a handy list of seeds to plant in September and October.

Vegetables – Snap Beans, Beets, Bok Choy, Broccoli, Brussel Sprouts, Cabbage, Carrots, Cauliflower, Celery, Collards, Cucumbers, Endive, Kale, Lettuce, Mustard Greens, Peas, Green Onions, Snow Peas, Radishes, Spinach, Swiss Chard (“bright lights” is pictured), and Turnips

Herbs – Catnip, Chives, Cilantro, Dill, Fennel, Garlic, Lemon Balm, Marjoram, Mint, Oregano, Parsley, Rosemary, Sage, Thyme

Flowers – African Daisy, Bells of Ireland, Bishop’s Weed, Black-eyed Susan, Calendula, Cornflower, Dianthus, Flax, For-Get-Me-Not, Foxglove, Gaillardia, Lobelia, Mexican Hat, Nasturtiums, Poppy, Primrose, Ranunculus, Salvia, Snapdragon, Stock, Sweet Peas, Verbena

Native Wildflowers – Plant your wildflower seeds in October for spring blooms. We are fully stocked with your favorities and blends.