Evergreen Wisteria

September 11, 2013

Never heard of evergreen wisteria? You're not alone! Many gardeners have never seen or grown this vine and I consider it a very underused ornamental. Millettia reticulata, while commonly referred to as evergreen wisteria, is not actually related to true Wisteria. This vine does have a similar appearance to true Wisteria, but instead produces gorgeous deep purple to magenta pea-like blooms at the tips of stems. The color is almost iridescent!

Millettia reticulata

This is a photo of my evergreen wisteria in bloom. The vine grows to approximately 15’ tall and 3-6’ wide, with dark glossy green foliage. Plants are winter hardy in USDA zones 8-11, but you'll find in Zone 8 plants may only be partially evergreen over the winter or may even drop all their leaves in a colder than average season. If they do defoliate, new growth will re-emerge from the dormant vines the following spring.

Evergreen wisteria needs a sunny location in order to bloom well, but can take some late-afternoon shade. Make sure to provide this vine with good support like a sturdy arbor or fence. Bonus: The blooms are fragrant!


Hot Climate Gardening: Watering in Summer Heat

August 14, 2013

Here are a few common questions I get about watering and watering systems, which are an important tool in very hot dry climates:

1. Sprinkler systems are expensive. Is it really worth the investment?
There are several reasons why a sprinkler system may or may not be right for you. If your landscape contains mostly woody plants and herbaceous ornamentals with little turf, you may want to stick with soaker-hoses/drip irrigation and hand watering. However, if you have an expansive lawn or you just don’t have the time to water, a sprinkler system may be the way to go. Turf requires deep watering in order to encourage a healthy root system. Hand watering or watering with mini-sprinklers usually doesn’t do the trick. A sprinkler system allows for proper and consistent watering with little effort. Because sprinkler systems are controlled automatically with timers, you can ensure your landscape won’t lay victim to drought while you’re on vacation in August! If you aren’t ready for an expensive underground sprinkler system, you may want to consider using an above ground stand-alone pulsating sprinkler, such as a Rain Tower. Stand-alone sprinklers are several feet tall and connect to standard garden hoses. In the long run, a good sprinkler system can increase the value of your home, which may make the investment a worthy one.

2. What kind of mulch is superior for moisture retention?
Most gardeners use organic mulches, which are derived from plant material, to conserve moisture in their landscape. Inorganic mulches include lava rocks, pebbles, plastic, or landscape fibers. Inorganic mulches can conserve moisture, but they do not break down to improve soil structure nor do they add nutrients. An important value of organic mulches is that they continuously add organic matter to the soil surface in addition to conserving moisture. Homemade organic mulches can be produced by recycling yard waste such as chopped or shredded leaves, wood chips, and dry grass clippings, or you can purchase mulches from your local garden center. Shredded hardwood mulch is an excellent choice if you are going to purchase mulch. Mulch should be applied as a 2-5 inch layer on top of your existing soil. Over-mulching will limit air and water movement to the soil and cause disease, so make sure not to over do it!

3. What is the trick to using soaker hoses?
Drip, trickle, or soaker hoses are ideal for use on woody plants, herbaceous ornamentals, and vegetable gardens. Soaker hoses use less water than conventional systems, such as the handy garden hose, operate at lower pressures than sprinkler systems, and save water by preventing run-off. Soaker hoses actually “sweat” water as opposed to spraying it into the air. The key to successfully using soaker hoses is to run them long enough. While you may be able saturate your soil to 6" deep by running a sprinkler system for 40 minutes; it could easily take 3 or 4 (or more) hours to get the same saturation with a soaker hose. Remember, it's a slow drip! One tip for using soaker hoses is to bury them underneath your mulch if you can. This not only holds the hoses in place, but also ensures that the moisture reaches the soil instead of getting trapped in the mulch. Soaker hoses are also very useful for keeping your foundation watered, which is crucial during our hot dry summers. Place the soaker hoses along the drip line of your home, or about 18 to 24” away from the foundation.

4. What time of day is best to water? As a general rule, how often and how deep should I water? As a general rule, how often and how deep should I water?
Early morning is the best time to water if you can. Watering during the evening or at night encourages fungal diseases on your turf and ornamentals. Watering during the middle of the day or afternoon can cause scorching. High soil temperatures also make it difficult for plants to take up water efficiently. When it comes to turf, the less often you water the better. Setting your sprinkler system for 10 or 15 minutes a day will do more harm than good. Shallow watering causes a shallow root system that is susceptible to disease and damage due to heat and cold. Water your turf about once a week for an hour early in the morning. In the heat of the summer you may need to increase to twice a week, but only if your grass is wilting (the blades will curl and it may have a bluish tint). Herbaceous ornamentals, such as your summer annuals, may need more frequent watering as summer progresses. Their root systems usually reach about 6 to12 inches deep, so check the surrounding soil every couple of days. Established trees and large shrubs only need supplemental watering during periods of drought, but newly planted trees should be watered frequently and deeply until they reach 2 to 3 years of age. Soaker or drip hoses are best used to keep your woody plants watered properly.

Be sure to abide by your city's water restriction guidelines!


Plant Nutrient Profile: Potassium

July 18, 2013

Fertilization and plant nutrients are often a mystery for many newbie gardeners...and experienced gardener's alike. While I find soil biochemistry and nutrient analysis fascinating, I'll bet that my soil chemistry books would substitute for sleeping pills for most. I get so many questions about fertilization and plant nutrients, I thought I'd start a series of plant nutrient profiles in order of importance. Don't worry, you won't have to read a thesis; I'll keep it simple and break it down easy so you can take the info and run with it in your own garden.

The third nutrient in the series: Potassium (K)

Peaches 2010

What does Potassium do? Potassium promotes flowers and fruits. Potassium helps with the formation of flowers and fruit, but it's also necessary for toughening growth, resistance to pests and diseases and drought and cold tolerance. Potassium deficiency is usually a problem on light sandy soils and is indicated by brown scorching on the leaves and curling of leaf tips.

When do I use Potassium? You can apply Potassium, or Potash (water soluble form of Potassium) in small amounts throughout the growing season, especially to veggie gardens and fruit crops. It is commonly applied to gardens, lawns and orchards as part of a balanced fertilizer. Greensand is a good organic amendment that includes Potash.

So, to keep it simple: Potassium = Flowers, Fruits & Vigor


Using Coffee Grounds in the Garden

July 16, 2013

There seems to be a lot of confusion about using spent coffee grounds in the garden. You can use coffee grounds directly in the garden, but as with anything, moderation is key.

Drinking really good coffee in Ecuador!

It's often stated that coffee grounds are acidic, and therefore good for acid loving plants like hydrangea and azalea. However, when coffee grounds are brewed they become close to neutral with a 6.5-6.8 pH; also, as coffee grounds decompose in the soil any acidity neutralizes...so the soil acidifying effects are nominal to non-existant. You'll see recommendations to add fresh spent coffee grounds directly to the soil around the plants. But how much? Typically, you never want to add more than about an inch worth of coffee grounds around base of the plant, to the drip line. Then gently work it into the top layer of the soil. Make sure these original coffee grounds are completely decomposed before you add any new grounds. Roses, hydrangeas, hollies, and azaleas are all good candidates for coffee ground amending, but you can use them for any plants in your garden.

So what do coffee grounds do exactly? Well, they are a source of Nitrogen. However, that doesn't mean that coffee grounds are an instant Nitrogen fertilizer. Rather, as they decompose and are broken down by microbes, Nitrogen will be released and available to plants. So it takes time. You should think of coffee grounds as more of a soil amendment, like compost, rather than a fertilizer.

Where coffee grounds really go to work is in the compost bin. If you've used the maximum recommended amount around your plants already, the leftovers should go into the compost. If you're not sure how to make compost, all you really need to do is balance your "greens" and "browns". The "greens" are your sources of Nitrogen. The "browns" are your sources of Carbon. So which category does coffee grounds fall into? GREEN! That's right; because it's a source of Nitrogen, you should consider coffee grounds a "green", even though they are brown. Other greens would be vegetable kitchen scraps, fresh green pulled weeks or fresh green grass clippings. Browns are made up of dried leaves, dried grass clippings, newspaper, wood ash, etc. To properly balance your compost, just mix a ratio of 1:3 of greens to browns, by volume. So for 1 bucket of "greens" add 3 buckets of "browns" to balance out the compost. This will ensure a proper balance of nutrient sources for the beneficial microbes that will break down the compost. Make sure your compost gets about a half day of direct sun and you keep it moist, about the consistency of a wrung out sponge. Turn your compost regularly to aerate it.

Now, go drink your coffee and stop throwing those grounds in the garbage can!


Plant Nutrient Profile: Phosphorus

July 11, 2013

Fertilization and plant nutrients are often a mystery for many newbie gardeners...and experienced gardener's alike. While I find soil biochemistry and nutrient analysis fascinating, I'll bet that my soil chemistry books would substitute for sleeping pills for most. I get so many questions about fertilization and plant nutrients, I thought I'd start a series of plant nutrient profiles in order of importance.

The second in the series is: Phosphorus (P)

Bavabeanbucketsm

What does Phosphorus do? Phosphorus encourages strong root systems and tubers; but it also assists in overall general health and fruit production by converting the sun's energy and nutrients into usable plant food. A Phosphorus deficiency leads to stunted, sickly looking plants and a lower quality fruit or flower. Phosphorus deficiency is not a huge problem in the home garden, but it is key to food and agricultural production. Think of Phosporus as something you'll mostly need to add in the vegetable garden. In certain soils Phosphorus may be plentiful, but bound up by soil particles and unavailable to plants. This is common in our heavy clay soils in N. Texas.

Often you'll hear recommendations to add no Phosphorus to your soils because there is already an excess (the water-soluable form of Phosphorus can be a big environmental and water quality problem.) But again, while you may have high levels of Phosphorus in the soil, it may not be available to your plants. Phosphorus exists in both organic and inorganic forms in the soil. Adding organic matter and stimulating microbial life can aid in the natural availability of Phosphorus. Soil microbes break down Phosphorus from its organic form to the inoranic form that is taken up by plants.

When do I use Phosphorus? It's best to use fertilizers that include Phosphorus on new plantings to encourage healthy root development. You can also apply in fall to the landscape to encourage root development over the winter. Animal manures provide Phosphorus and stimulate microbial growth, so they can often be a good soil additive for your landscape and vegetable garden; and a more desireable substitute for highly concentrated synthetic forms of Phosphorus.

So, to keep it simple: Phosphorus = Roots & Tubers


Plant Nutrient Profile: Nitrogen

July 3, 2013

Fertilization and plant nutrients are often a mystery for many newbie gardeners...and experienced gardener's alike. While I find soil biochemistry and nutrient analysis fascinating, I'll bet that my soil chemistry books would substitute for sleeping pills for most. I get so many questions about fertilization and plant nutrients, I thought I'd start a series of plant nutrient profiles in order of importance. Don't worry, you won't have to read a thesis; I'll keep it simple and break it down easy so you can take the info and run with it in your own garden.

The first in the series is of course: Nitrogen (N)

Cilantro

What does Nitrogen do? In basic terms, it promotes leafy green growth. Plants typically need a good amount of Nitrogen to thrive. Nitrogen is fast acting, promotes the growth of leaves and other vegetative green growth. A Nitrogen deficiency produces pale or yellow small leaves, weak growth and spindly shoots. Too much Nitrogen can stunt flowering.

So when do you need to add Nitrogen to your soil? At the beginning of the growing season in early spring, and then several late-spring and summer applications to turf grass and veggies. In warm climates you can also add Nitrogen to all plantings in early fall, but not too late: New leafy growth encouraged by Nitrogen is more suceptible to frost.

Nitrogen can be added in liquid form or granules. Liquid forms will be taken up by plants right away, so they are good to use if your plants are Nitrogen deficient. But they don't persist in the soil. For a slow release effect, use a granular form. Organic fertilizers typically top out at about 9% Nitrogen, but you can apply them regularly without fear of damaging your plants. Blood Meal is a good source of Nitrogen. Animal manures such as cow, turkey and chicken manure, will naturally provide about 18-22% Nitrogen so they are a great boost especially for veggie gardens; but they can burn plant roots if used fresh; compost manures for best use.

Legumes and Vetches, such as peas and fava beans, can fix atmospheric Nitrogen in the soil. They form a beneficial union nodes in their roots with soil bacteriain the genus Rhizobium, which help convert Nitrogen into a form useable by plants. Rotating legumes and vetches around your garden is a great way to provide free Nitrogen.

So, to keep it simple, Nitrogen = Green.


Lavender that thrives in North Texas

June 20, 2013

Lavender plants like dry hot conditions...so it may seem like a no-brainer that Lavender should perform very well in Texas, right? Well, not so...Here in North Texas, we have particularly heavy clay soil that doesn't drain well when wet. This is the kiss of death for most lavender plants. Many Lavender plants don't even make it through their first year planted before they succumb to exces moisture.

Lavender goodwin creek

There are some varieties that perform better than others. I've had particularly good luck with this 'Goodwin Creek'. Of course, you should alway plant your Lavender "high and dry" meaning plant it in a higher spot in the garden, so it receives better drainage, and don't plant it where it will receive excess irrigation. Plants need to dry between waterings. You can topdress your plants with expanded shale to keep moisture away from the crown of the plant. Always plant in full sun. If you've struggled with growing Lavender in the garden, give it a try in containers.

Lavender is also a favorite of the bees...bonus!


Malabar Spinach: Heat Tolerant Leafy Green

June 17, 2013

An Unusual Spinach Substitute

For those of us that live in warm climates, we can't grow things like spinach and tomatoes at the same time....we actually have to split our edible growing seasons into "winter" and "summer". Spinach and other leafy greens thrive from fall through winter, but quickly bolt as our summer heat comes on. So how do you manage to keep in fresh leafy greens from the garden year round? Look for alternatives to the cool season greens; like Malabar Spinach.

Malabar spinach1

This beautiful warm-season vine produces fleshy edible spinach-like leaves on purple stems all summer long. Now, it doesn't taste exactly like spinach, but that might be a bonus to some at it has a milder flavor. You can use it just the same as you would spinach; by cooking older leaves and using small young leaves in fresh salads. Not to mention, it's a beautiful ornamental. I grow mine on decorative trellises or other supports.


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