The color of light isn't just important for photosynthesis

No new growth. It is normal for rhododendrons and azaleas to have new growth every spring. However, this won't happen if the plant is not healthy and doesn't have enough light. Light is necessary to encourage bud formation for both flowers and foliage. Low light encourages upward, tall, gangly growth. However if the light is too low, the plant has no vigor. Also, proper , , , and are necessary for general plant vigor. [

There is evidence that all eight members of the vitamin E family are required in health.
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When: For most garden situations the old rule "once before they bloom and once after they bloom" is still a sensible approach. Actually the fertilizer timing has nothing to do with the time the plant flowers, it simply means once in the early spring, probably April then again in June. Never fertilize after mid-summer. Over-fertilizing is worse than not fertilizing at all. Established azaleas often do well with no fertilizer at all. Nutrients are slowly released by any organic mulch that you use, so rely on this as the primary source of nutrients. Excess nutrients may promote larger than normal populations of azalea pests like lace bugs and azalea whiteflies. It's very easy to burn up the fine roots. Fertilizing after late June in a northern climate promotes tender growth in the fall, which doesn't harden off before the first frosts of winter. This tender growth gets killed by the frost. This growth may have the buds for next year's flowers on it, which would also get killed by the frost. Research indicates that plants reasonably well supplied with nutrients, including nitrogen, are more resistant to low temperatures than those that are starved.

which is necessary for animals to breathe.

This may cause certain insect pests laying eggs in the fall to seek another host plant for their offspring that is weaker and drab by comparison.
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Phytophthora Dieback, The oomycete, or water mold, Phytophthora causes one of the most common disease problems in the landscape for rhododendrons and azaleas. This oomycete is a "water mold," and thrives in poorly drained or wet conditions. A wilted plant is usually the first sign of trouble. Rhododendron leaves will curl inward and droop. Drought can cause similar symptoms. Roots of affected plants appear soggy or blackened, and the outer portion of the root easily pulls away from the inner portion. Crown rot causes the lower portions of the stem to have a brown discoloration of the wood near the soil line. This disease is favored in poorly drained areas or when plants are set too deeply. Plants may remain without symptoms until further stressed from drought or flooding. Azaleas. Resistant: R. sanctum, R. simsii (Indian azalea), R. yedoense var. poukhanense (Korean azalea), 'Corrine,' 'Fakir,' 'Fred Cochran,' 'Glacier,' 'Hampton Beauty,' 'Higasa,' 'Merlin,' 'Polar Sea,' 'Rose Greeley'. Moderately resistant: 'Alaska,' 'Chimes,' 'Eikan,' 'Jan Cochran,' 'Morning Glow,' 'New White,' 'Pink Gumpo,' 'Pink Supreme,' 'Rachel Cunningham,' 'Red Wing,' 'Shinkigen,' 'Sweetheart Supreme'. Rhododendrons. Resistant: 'Caroline,' 'Martha Isaacson,' 'Pink Trumpet,' 'Prof. Hugo de Vries,' 'Red Head,' R. davidsonianum, R. delavayi, R. glomerulatum, R. hyperythrum, R. lapponicum, R. occidentale, R. poukhanense, R. pseudochrysanthum, R. quinquefolium and R. websterianum. Do not set new plants any deeper than the original soil level. Ensure the root collar is exposed and free of soil and mulch. Rhododendrons and azaleas are subject to collar rot when root flares are buried. When planting in poorly drained soils create raised beds or provide sub-surface drainage. Plant with the root collar exposed. If soil is compacted, prepare planting area by cultivating and incorporating organic matter. Firm the soil slightly at the base of the planting hole to prevent the plant from settling into the bed. Also, keep the mulch back 2 to 3 inches from the stem. Do not plant azalea and rhododendron plants into sites where plants have previously died from root rot. Even resistant plants may succumb under these conditions. The oomycete survives in the soil and cannot be eradicated once an area is infected. Also see , and .

Photosynthesis Terms Flashcards | Quizlet

Pinching: A friend of mine has the most beautiful rhododendron and azalea garden. All plants are about waist height. From any place in the garden you can see just about every plant. During the flowering season it is awesome. I asked him how he keeps the plants so well kept and his reply was that he just removes the top foliage buds each year with his fingers in the late fall or early spring. This can be done once the rhododendrons reach the height you want. Then each spring after the flower buds start to swell and the smaller leaf buds are obvious, break off leaf buds [pinching] on the top of the plant to prevent it from growing taller. You must be careful not to damage any flower buds. No pruning at all. This technique minimizes disease and insect damage. It works very well for him. It is labor intensive, but well worth the effort.

Terms to know for photosynthesis quiz for Honors Bio

With the larger leaved rhododendrons (elepidotes), you must prune just above growth joints. Each year as the plant starts to grow there is a visible point where the plant started growth. We call this point a growth joint. Prune just above this point, because that is where the dormant growth buds are located. Don't prune between joints, because there are no dormant growth buds in that area. However, with azaleas and the small leafed rhododendrons (lepidotes), you may prune anywhere along the stem, though you may not be able to see them, these plants have dormant growth buds nearly everywhere.