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Mathematics In The Garden
Welcome through Fred's Garden Gate! Right now is one of the best times of the year for perennial gardeners to practice a little old-fashioned arithmetic. You can add to your collection of plants by multiplying those you or your neighbor already have and subtracting the old, rotted or deficient center parts, thereby accomplishing what is commonly called division. Our 13-year old grandson said, "C-o-o-o-o-l!"
Yes, fall comes pretty close to being the ideal time to divide almost all perennials - with few exceptions. Here's a general when-to-divide rule: Dig and divide during the season opposite the season of heaviest growth and flowering. So. . .if it blooms in the spring or very early summer, divide in the fall; if it blooms in the fall, do your digging and dividing early the following spring. Rules, however, can be "bent" a bit here and there, especially if plants need rescuing or must be relocated due to a family move.
This time let's take a look at some general principles first, then go to some specifics about a few common garden perennials in the next article in this two-part series. . .so get ready to "do your math."
When will they need dividing? Given good care and seasonal feeding, most perennials will remain healthy, attractive and productive for between three and five years without being disturbed. Beyond that, they'll become far too crowded, parts of the original plant will have dwindled or died out, or they'll just not look good any more and flowers become progressively smaller and more sparse.
Always select a cool and overcast day to do your dividing. You're about to scare your poor plants half-to-death, and it won't do them the least bit of good to allow them to dry out in the heat, wind and sun.
Keep a hose or pail of water nearby to wash soil from roots, to rinse your hands and to immediately water-in the newly-divided and planted results.
PREPARE THE SOIL
While this crucial step is the single most important step in creating or rejuvenating a garden, it is sadly the most universally neglected. Think about it. . .you're about to install some very expensive plants into a new home where they'll be required to endure several years locked tight to the spot during drought, possibly flood, malnutrition, abuse and maybe even general neglect. They'll be expecting to sink their roots deep into rich, chocolaty-brown earth literally alive with biodiversity and nutrition. How would you feel if someone plunked you into dense, shallow, unimproved, sticky clay or contractor-fill with no real food (an occasional sip of Miracle-Gro doesn't count!). . .and be forced to barely survive for the next half-decade?
No? You wouldn't like it? Neither will your plants. . .and you'll like the way your plants perform in improved (really improved) soil a lot more, too. Now, having been forced to sit through that sermon, let's get to work.
Make certain that all weeds, roots, stones and harmful soil insects like white grubs, slugs, cutworms and the like are removed or destroyed. Remember that plants like it rich, deep, moist and in the right light, and they love to eat! Adjust soil pH by adding lime, ashes or whatever is needed to bring it to between 6.5 and 7.0. Some perennials appreciate a different pH, so consult a good book. Add in a generous amount of compost or old, well-rotted manure and spade it all in just as deep as you can get it, mixing all components throughout the full depth. A generous helping of deodorized bone meal and some fertilizer - either granular or its organic equivalent - should be incorporated into the total soil foundation. . .not simply sprinkled on the surface.
MAKE A PLAN
Most folks overlook this important step, mostly leaving their garden somewhat arbitrary and haphazard. Consider color harmonies, height, spread over the next three to five years, length and season of bloom, shade that may be cast on shorter plants by taller ones, angle or direction of view and your own artistic inclinations. Perhaps you could share a two-sided garden with a neighbor. What a very nice way to be a good neighbor!
Don't forget paths and stepping stones, borders or maybe some stone work. Anything you can do to make your new garden site more pleasing and attractive now will not only increase your pleasure for the next few years, it will also certainly add to your property's salability should you ever decide to sell and move on.
GATHER TOGETHER YOUR TOOLS
Locate and assemble your hose, pail, shovel, trowel, sharp and stout knife, a rugged pair of scissors or snips, some fresh labels and a marker, gloves and knee pads - if you have them - compost, fertilizer and lime, and finally your plan or sketch.
NOW...LET'S GET TO WORK!
Now that plans are made and tools are assembled, let's take a closer look at a few specific - popular - perennials, and exactly what it'll take to get the job of dividing done right.
DAYLILIES - When the plants are about two or three inches tall, use something like a manure fork to pry the entire clump out of the earth and set on level ground. Being careful not to damage new growth, bounce and shake it to remove most of the old soil. I sometimes use the water hose and a nozzle to thoroughly wash roots clean. Some gardeners use two manure forks inserted back-to-back down the center of the clump to pry it apart. I prefer to wriggle and twist and pull the whole thing apart with my hands if possible. Occasionally, I'll use a sharp, rigid knife - being very careful not to cut towards my tummy or fingers. The photo at the right shows one of Hill Gardens of Maine's own hybrids, Hill's Icy Sue...a cross between H. Ice Carnival and H. Jenny Sue...a lovely near-white with a delicate, soft, pink blush and a subtle, sweet fragrance. Don't you just want to reach out and touch it?
Reduce the clump down to two or three "eyes" per division, exercising caution not to damage too many of the soft, long, radish-like roots. Replant the clump in the newly-revitalized location to which some extra lime or wood ashes have been added, spreading the roots out and tamping soil firmly to eliminate large air spaces. The point at which the root actually meets the growing point should be no more than one inch below the surface after all is said and done. Now water each plant well enough to completely saturate, then label. Don't forget to rebuild the soil in the spot where the original clump was removed before you replant that spot. For much more on the subject of these great sun-loving perennials, visit: All You Need To Know About Daylilies!
DELPHINIUMS - The process is almost exactly the same as that for daylilies, except delphiniums want much more manure or compost, a healthier dose of bonemeal and a little more lime. They prefer a slightly alkaline soil and will not look their best without the added lime. Space new plants about 18-inches apart and at the same depth as they were. Remember to be somewhat more gentle since early growth will snap off quite easily.
TALL GARDEN PHLOX - These can be a bit tougher because they tend to make very dense, solid crowns. Be brave, however - there is little you can do to slow down a phlox! Dig when the first sign of spring growth appears. Shake or wash all the old soil from roots, and use your knife to chop the clump into manageable sections. I like to leave five or six "eyes" or shoots per division. Replant them immediately so they don't dry out, at about the same depth as they were. If any roots break off, shallowly plant them as well, for new plants will likely arise from them. Give garden phlox plenty of space in the sun - two-feet or more between plants.
BLEEDING HEART - Dicentra will need to be dealt with a little earlier, since they often emerge a week or two before most others. They can be divided when they're upwards of a foot tall. . .but I don't recommend it because the tops are very fragile and snap off at almost the slightest touch.
Bleeding hearts have long, thick, fleshy roots, so start digging about a foot or more all away from the plant to retain as much root length as possible. Carefully shake away most of the soil and gently pry or cut the crown apart, leaving two to four eyes per division. Replant immediately with a little more compost or old manure and plenty of bonemeal mixed in the bottom of the hole. Space out two or three feet apart and plant at the same depth as before, spreading the roots out carefully and well. If any loose root pieces remain, put them in the top layer of the planting, an inch or two deep, then water the whole spot well. For more about Dicentra, visit: Bleeding Hearts.
HOSTA - are best divided at the very first sign of growth in spring. I prefer to dig with a manure fork to avoid cutting any more roots than necessary. Shake all old soil from the root mass and, using a strong, sharp knife - and being very careful around fingers, belly-buttons and knees - reduce the clump to pieces with no less than three or four "eyes". Avoid slicing through roots. Hosta prefer a sweeter soil for optimum performance, so add generous amounts of fresh compost and lime (or wood ashes) before re-planting. Space small-to-medium hosta about 12 to 18 inches apart; larger varieties 18 to 30 inches. Remember to spread roots out in an oversized hole - they don't like their ample "feet" jammed into tight shoes, so to speak. For much more about shade-loving hosta, go to: All You Need To Know About Hosta! The photo at left shows H. Wide Brim. Note the rich, chocolaty-brown soil. That's what keeps a hosta looking fine!
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