Friday, April 22, 2011

Perennial Preening

Slugs are the number one maintenance issue for PNW gardeners. I use a multiple phase strategy. First line of defense is iron phosphate bait which I try to put out twice a year, in April and October. Secondly, I go after IMG_0004individual perpetrators. I keep handy a spray bottle with 1/3 ammonia and 2/3 water and search for slugs in the cool of early morning or after a rain. It is worth it to pay the extra money for a sturdy bottle; I can hit a 4” slug at 20 paces. Last line of defense is the mollusk keg party. Use a small plastic container, such as a 6 ounce drinking glass, yogurt or margarine tub. Half bury in the soil and fill with the cheapest beer you can find. Read way more about slugs in this previous post.

Weeds will stage a coup and take control of your garden if not fended off. If you remove the weeds before planting and mulch after, your weeds will be manageable. 2-4” of mulch is plenty; it will also retain moisture and promote consistent imagesoil temperature. Many gardeners, especially in very cold areas, mulch in the fall to regulate the soil temperature and protect roots from frost-heave. Here in the mild PNW we don’t have a big problem with alternately freezing and thawing ground heaving plants out of the soil. I mulch in late winter for weed suppression and moisture retention. Remember that if you decide to use bark, you must add nitrogen to compensate. The decomposition of the bark uses all the available nitrogen in the soil. If you use compost, you are improving your soil every time you mulch.

Deadheading has nothing to do with rock bands and hippie vans. In gardening vernacular, deadheading is simply removing spent flowers. It keeps the garden looking fresh, promotes reblooming and prevents reseeding. Most plants will continue to bloom until they are allowedimage to set seed, so removing spent flowers encourages new blooms. Remove any dead leaves at the same time; some folks call this ‘dead-leafing’.

Pinching is cutting back all of the branches of the plant by 1/3 to 1/2 to promote bushier growth and more blooms. This is particularly effective with chrysanthemums and asters. I used to actually pinch these plants one branch at a time. I’ve learned that they respond just as well to whacking with pruners or even sheep shears. Thinning is a different process. To thin, remove 1/3 or more of individual stems of a plant to increase air circulation. This is commonly done with plants susceptible to mildew, such as phlox paniculata.

Staking is nobody’s favorite garden task. However, If you insist on growing imagedelphiniums you will have to stake-unless you grow the less common dwarf varieties such as D. ‘Blue Butterfly’ or D. nudicaule. If you must stake, do so early in the season so that the plant grows up gracefully around the stake. If you wait until the need becomes obvious, your plant will look like a hog-tied rodeo calf for the rest of the season. To reduce staking, use the right plant for the place. Not enough sun or too rich soil can make a plant leggy. Look for dwarf varieties. Pinching or cutting back will keep you from having to stake asters. Use supportive companion plants if possible. I sometimes use deciduous azaleas to support floppy late summer bloomers. DO NOT use a conifer to support another plant. Overlaying vegetation will cause damage or death to conifer branches.

During the season, and especially after frost, remove debris from the beds. Remember that anything diseased should be destroyed. If you leave it in the garden, you will surely see the problem again next year. Everything else can go into the compost for next imageyear’s mulch. You may also want to cut back your perennials, but be judicious. Some of the seed heads, pods or sturdy stalks are architecturally interesting and can attract birds to your garden to entertain you and provide some late season pest control. Ornamental grasses provide interest and movement in the winter garden and, in any event, they are petulant if you cut them back before spring. Like some perennials, notably chrysanthemums and fuchsias, they will overwinter more successfully if you leave at least 10” or so of growth. A great resource on maintaining your garden is The Well-Tended Perennial Garden by Tracy DiSabato-Aust.

Because our summers are dry, watering will be an issue. Be wise with your water. Thorough, infrequent watering will encourage deep root growth so imageplants can survive a dry spell. Avoid planting water hogs, unless you have a bog. Remember to choose the right plant for the place. Don’t plant a hosta in full sun. Given enough water, it will survive, but why waste the water and the time? Consider xeriscaping; once limited to places like Arizona, it makes sense to consider drought tolerance everywhere. Check out local examples like the drought tolerant section at BBG. High Country Gardens is a great educational tool about plants suitable for xeriscaping. Do be careful to avoid plants that cannot stand wet feet in winter if you are gardening in the Pacific NW. To determine if you have a problem, try this percolation test.

Division becomes necessary when bloom reduces or the center of the plant dies back. To keep the plants vigorous, you divide them and discard the center-with the added benefit of creating more plants.  You don’t have to wait for center die out; any plant that has grown larger than the place you have it planted may be divided. If it blooms in the spring, divide in the fall; if it blooms in the fall, divide in the spring. For more information, see this earlier post on division.

If all of this sounds like a lot of work, remember it is spread out over about 9 months. If you compare the investment in maintenance of perennials with the maintenance of a lawn, you will find that flowers are bargain.

Saturday, April 9, 2011

Picking and Planting Perennials

Once your beds are ready, you start the hunt for the perfect plant varieties you have carefully chosen as you were making your garden plan. One of the challenges and also the greatest satisfactions in gardening may be in creating pleasing plant combinations which together have a greater impact than the individual plants.

Look for your plants at local nurseries and plant sales. The Snohomish County MG Plant Sale is typically imagethe Saturday before Mother’s Day, so this year it is May 7, 2011. The Miller Horticultural Library lists plant sales and other plant sources on their website. Sometimes you can find a hard to locate plant by mail order; be SURE to check out all online and mail order nurseries at a consumer watchdog site such as this one.

Make sure the plant you want to buy looks healthy and free from visible pests. Plants with discolored, curled or wilting leaves should be avoided; look under the leaves, too. Check the tag-some plants are supposed to have unusually colored leaves. The plant should be the right size for the pot; why pay for a 4” sized plant in a gallon pot?  Do not be afraid to carefully slip the plant out of the pot to check the roots which should be pale and clean looking.

If the roots wind tightly around in the pot, the plant is root bound. Sometimes, I find a plant for which I’ve long been searching and it is root bound. If it a good price and looks otherwise healthy, I’ll buy it. It will require more TLC at planting, but I’ve rarely been disappointed. Remember that smaller pots are cheaper than larger and by the end of the season there will be little difference in size of the plant. Keep your plants well watered and out of full sun until they are planted.

If you are starting in early spring, make sure the ground is not too wet to plant. Pick up a good size handful of soil and squeeze it together. If it sticks together, you need to wait a bit longer. If it falls easily apart, the soil is ready to work. I’ve seen workable soil described as having the texture of chocolate cake, but that is self-defeating as it just makes me want to hang up my tools and go bake.

Cool misty days are perfect for planting and we have lots of those. However, I’ve been known to move a rose bush in full bloom in the middle of August at noon and have it survive. PlantsIMG_0002 are sturdier than we think. Plan before you plant-you may want to place the plants in their pots in the places where you intend to install them. Be sure to allow space for the mature size of the plant. Plants should not be planted closer than the sum of their width at maturity divided by 2.

Dig the hole and, unless the soil is already damp, fill the hole with water. Allow it to drain completely. (This previous post discusses what to do if it doesn’t drain-but hopefully you have already determined the drainage quality of your soil.) Soak the plant-still in the pot-in a bucket of water until the bubbles stop. If you have opted to buy a plant with a solid root mass, slice downward around the edges of the root ball to encourage outward growth. Plant at the same level as in the pot, firm it down and water well. If the weather is hot and dry, make a rim of soil around the edge of the hole at soil level to hold the water directly over the root ball as it soaks in.

If the soil has been amended with compost, no fertilizer is needed and might burn the roots if used. Osmacote is an example of a slow release fertilizer that won’t burn roots, but remember that it does not begin to work until the soil temperature reaches about 70°.

yard523 015Keep an eye on your new plants for a week to 10 days, especially if it is hot, sunny or windy. A delicate specimen may need to be shaded for a few days if the sun is intense. Even drought tolerant plants will need consistent water during their first season in your garden.

Sunday, April 3, 2011

Make Your Bed

After you are satisfied with the plan for your garden, you need to prepare the soil. Soil is the most crucial element for gardening success. An old adage states “for every $10, spend $9 on soil and $1 on plants.” This seems counter-intuitive. However, a mediocre plant will thrive in excellent soil, while in poor soil an expensive, great looking plant will decline. See this previous post on the mysteries of soil.

Soil holds water, nutrients and organic matter that are required by plants. Soil is made up of particles; “loam” is a mixture of the two most common particles. Sand is the largest; it drains the fastest and has limited ability to retain moisture and nutrients. Clay is the smallest; it drains very slowly-if at all. Some clay soil is so tight it practically forms a clay “bowl” when you dig a hole in it.

In addition, plants require air, so it is important that the soil is not compacted. If there is not enough air in the soil, plant growth will be limited and the plant imagemay die. Compost improves every kind of soil. Compost helps sandy soil to hold moisture and it breaks up clay, allowing moisture to drain. In all kinds of soil it provides air pockets and micro-organisms which are vital to the health and arability of your soil.

If you are creating a garden from lawn or unworked soil, the first step is to mark the outline you desire with a length of rope or garden hose. If you read the great garden books out of Great Britain, you will learn that the classic method to prepare a new bed is double digging. There is now some debate in the gardening community about this practice, but it has worked for generations. And WORK is definitely the defining word here.

More recently, a new practice has been espoused that is less daunting. When I first heard of this, the thinking was to use glyphosate on the grass or weeds within the outline and cover with black plastic for a season-typically, over the winter. However, I like to avoid the use of chemicals as much as possible.

My experience shows that you can actually do just as well by covering your marked area with several layers of newspaper, thoroughly wet down, and then piling on amended soil. In a few months, the area should be ready to plant. If the area will accemay 2 09 001pt enough soil to plant in-such as in a raised bed- you may plant immediately. The newspaper lasts long enough to kill the plants below it, but is permeable to water and eventually biodegrades. I have used this method for replacing a lawn and also for creating an island bed within a lawn.

However you decide to prepare your bed, you must mark your outline, remove rocks and weeds and loosen the soil. Add compost to your soil to prepare for planting. If the soil is good, a 2-3” layer raked in should be enough. If the soil is very bad you may add up to 50% compost. DO NOT plant in 100% compost. If that makes you curious, check out this previous post.

Friday, April 1, 2011

Elements of Design

As you begin to create the design for your garden, keep in mind what will best grow there. For example, if you must have roses, make sure your site has good drainage and at least 4-5 hours of sun. IfIMG_0069a you don’t have full sun, your rose options are limited and if you have mostly shade, you will need to enjoy your neighbor’s roses, because they aren’t going to grow in your garden. If you want to grow delicate woodland ephemerals, you must have a protected shady area, accessible in early spring. (Check out this post on Epimedium.) If you lust for lavender, your drainage must be perfect. If your ground stays soggy, plant a bog. Sometimes you have to go with the flow.

Try to populate your garden with plants that will excel. Look for long life, strong but not overly vigorous, long bloom period, attractive without bloom, pest and disease resistant and tolerant of dry summers and weimaget winters. Great Plant Picks is an educational plant selection resource from the Miller Garden that suggests plants with those characteristics specifically for the PNW.

Intrinsic to good design is inclusion of a variety of sizes, shapes and textures which provide interest. Peter Dale, a writer and gardener from the UK called design, “the thoughtful settlement of the competing claims of variety, on the one hand and unity on the other.” Remember that foliage is as important as bloom and more lasting; learn to attractively contrast foliage. Pair foliage that is bold/delicate; big/small; light/dark; shiny/fuzzy; rough/smooth. Photo0202

Also consider the scale of plants to each other and of plants to property. Experts urge planting perennials in groups of 3 or 5; this provides a greater impact in a large bed. One plant of each kind is a collection, not a design. But, remember that the scope of massing should be in relation to the size of the space you have. In a small bed, you may not have room to mass groups together.

Harmony is an important design element that includes both repetition and color theory. When you repeat a plant or a group of plants through your design, it creates a sense of unity. Repetition also draws the eye through a design and ties it together.

Consider what will be visible at any given time and try to select plants that provide visual and sensory variety for that season. Photo0200Choose colors that complement and do not clash for concurrently blooming plants. Try to mix seasons of bloom so that you have interest all year long.

If you desire plants that are fragrant, try to site them so they are accessible-near your pathway, front door, or sitting area. If your fragrant plant blooms in warmer months, consider planting it next to a window that you may open. Also, be wary of planting two fragrant plants together as their fragrances may clash.

I’ve only scratched the surface of the vast topic of design but I hope I’ve piqued your interest. It may seem like there is a lot to consider; I confess, I’m a spontaneous gardener. I rarely return from a nursery without a new acquisition and no idea where to put it. Even so, I’ve learned from experience that if you take the time to design your bed in advance, you will be more satisfied and have less work than if you plant on the fly.

On the other hand, remember that your garden is always changing and don’t be afraid to experiment. Mistakes can be very educational.