Light – Xtremehorticulture

How to Get Rid of Snails in a Lawn

Leave a Comment / Light, slugs lawns, snail lawns, water / xtremehorticulture

Q. I have some snails in my lawn. How do I get rid of them? Snails like it wet and darker than most lawns. A. The best way to control snails (or slugs) in lawns is to give the lawn more light. Snails hate light but they like to eat! Snails and slugs eat young plants and microscopic plants such as “large enough to see” algae. The worst situation for snails and slugs is lawns growing under trees producing shade. The bigger and denser the tree gets, the more shade it produces. Dappled shade produced by the branches of trees may need to be thinned if it gets too dense. Snails and slugs hate sunlight, prefer shade, and wet soil. Right now there is enough light for the lawn as well as snails and slugs….if the lawn is kept wet. In cases like that, get rid of the lawn, or both, but in the desert never favor the lawn over the tree. A good-looking fescue lawn uses a lot more water than nearly any tree and usually requires daily applications of water in the summer. Fescue lawns in the shade of a tree might still need 6 or more feet of water annually to look good. Many of our trees in full sun will need anywhere from two to 5 feet of water applied under their canopy. Xeric trees like acacia need less water, annually, than mesic trees like pistache or vitex. Snails and slugs in lawns There are baits made for snails and slugs. Those baits usually contain iron phosphate which is low in human toxicity. But it is a pesticide. Sluggo is the old tried and true chemical control for snails and slugs. If you are into organics, then you might not want to use Sluggo. Your only options are to increase the light and trapping. During times of high light levels snails and slugs look for places to “hide” so laying out boards or other places so they can hide during the day provide places where they “collect”. Their numbers can be reduced if you are willing to dispose of them after they collect during the day such as under something.

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Plants Grow Toward Light

Leave a Comment / growth, Light, plants / xtremehorticulture

Q. I pulled out my old, bent crepe myrtle and bought a new one from a grower. It’s still small, but I noticed the “trunk” is already curving. Is this going to be a problem like the old one? Is there something I should do now, or will it straighten itself out as it grows? When I plant it, should I put the root ball in the ground at an angle so the trunk is pointing more or less straight up? Pine tree leaning due to shade on its West side from the eucalyptus. A. As soon as you plant it, the new growth will start straightening (bending toward the light) as it grows. The light will come at it from all different directions than in the nursery. When you plant it, plant it as straight as possible and let the plant figure it what is straight with its new growth. You can help it “straighten out” with pruning. As you guessed, the plant will figure it out as it grows. Pine tree leaning. What is not known to you is that there was a large tree that burned down (died) last year to the left side of that tree on the other side of the wall. That’s why it is leaning. Leaves and buds are light receptors. The side that is open will “fill in” with new growth as long as the plant gets enough light, water and fertilizer to push this new growth. The top growth from leaves and buds (where it “sees” light which determine where and how stems develop) is what we call “positively geotropic” which means it “grows up”. Roots are “negatively geotropic” which is a fancy way of saying roots “grow down”. Of course, root growth is encouraged by water, air, and fertilizer. Top growth is encouraged mostly by light but heavily influenced by irrigating and applying fertilizer to push new growth.

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Yellow Leaves on Potted Myer Lemon

Leave a Comment / fruit trees, lemon, Light, watering / xtremehorticulture

Q. I have a Myers lemon tree in a pot on a south facing patio. The wall near it faces east and there was a large pine tree out front so it receives shade in the afternoon. There are quite a few yellow leaves that just appeared. All the new fruit has turned black. It seems to me that maybe I just need to replace this tree. The lime tree is doing very well in a similar location. A. The picture you sent to me shows a Myer lemon with ready to harvest fruit being grown in a small container with smaller plants growing around its base. Meyer lemon typically flowers sometime in January and February. The fruit can be harvested starting about now (December) with this harvest, finished by January, encourages new flower development for next year’s production. Producing flowers and then fruit in midfall is early for Meyer lemon. Early flower development can be a sign that it is under some sort of stress. Certainly it’s not normal for this type of tree at this time of year. All fruit trees and vegetables need a minimum of six hours of full direct sunlight. 8 hours is even better. In home landscapes the best sunlight for it in our hot climate in the summer months is during the cooler morning hours. Partial shade may be pleasant for people sitting on the patio but not for many plants that produce fruit or vegetables. If shade is present during most sunlight hours, then I would recommend an ornamental plant for that spot with variegated or colorful leaves, not a flowering or a fruit-producing plant. A non-flowering ornamental handles shade better than a flowering plant, whether those flowers produce fruit or not. Don’t Plant Annuals at the Base of Perennial Trees Secondly, and perhaps more importantly, are the smaller plants demand for frequent watering compared to the tree. Growing a shallow-rooted plant or plants at the base of a deeper-rooted plant is a big “no-no” regarding how often water is applied. Shallow-rooted plants “signal” they need water applied more often than deeper-rooted plants, so they get water applied more often than the watering frequency needed for deeper-rooted plant needs. This type of watering can suffocate the roots of a deeper-rooted plant. Watering a deeper-rooted plant too often can produce leaf drop, flower drop, fruit blackening, and a tree that’s “loose in the soil”. Trees that develop “collar rot disease need to be staked after just a few years of growth. Does that sound like your fruit tree? I would replace this tree with a plant that requires moderate to low levels of sunlight. If you want to grow other plants along with it, select plants with a similar rooting depth and need for applied water.

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Loss of Pine Limbs May Be Light or Water

Leave a Comment / Light, Pine tree, water / xtremehorticulture

Q. I have a large pine tree in a natural area losing limbs from the bottom up. It’s needles are browning and dropping. I don’t water the tree much at all, but I have a water channel flowing 3 feet away on one side of the tree. The channel is mostly filled with moving water and is about 1 foot wide. A. It’s probably either water or light issue. Not enough light because trees are planted too close together will also cause lower limbs to die and drop. Sometimes light is not considered. Pine trees planted four to six feet apart are too close together and lower limbs will die as they age. An open canopy pine tree signaling that maybe the tree was either not receiving enough water OR it cannot get the applied water to the needles due to trunk damage. My guess is that it’s water related; not enough. An easy way to find out is to put a sprinkler on the end of a hose and give the tree one to two hours of water once every three weeks to a month. I would use a non-oscillating sprinkler and adjust it to about 8 feet wide. Use a four foot long piece of rebar to adjust how many minutes to water. Hose-end sprinkler. There are two ways that I use to tell if a pine tree isn’t getting enough water; 1) I look at the amount of new growth and 2) its canopy density. On well-watered, fertilized smaller pine trees to about 20 feet tall, I like to see about 18 inches of new growth and a solid canopy density. On older well-watered pine trees 40 to 60 feet tall the growth will be a lesser amount, perhaps 8 to 12 inches, but the trees still have a dense canopy. If growth is 2 to 4 inches when the pine tree is older then growth is not enough. Measure growth at the end of May after spring growth is finished. Pine trees with drought problems usually grow 2 to 4 inches in length each year. This small amount of growth translates into a very open canopy. Because pine trees can have other problems as well such as borers and woodpeckers (sapsuckers), I inspect the trunk for this kind of damage as well. A tree trunk with extensive damage by borers or woodpeckers may also show signs of drought. Pine trees with only a few inches of new growth each year and an open canopy usually suggests drought.

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Fig Fruit Production Not on/off Switch

Leave a Comment / fig, fruit tree, Light, sunlight / xtremehorticulture

Q. Would a fig tree produce figs if it got sun in the spring, fall and summer months but not the winter? I have lots of spots to plant trees but a house blocks winter sun. The amount of light and the quality of light is important in flower and fruit production as well as increasing the branching of some plants. All plants have a minimum amount of light required to flower and maintain fruit production. The amount needed varies among plants but generally most of flowering and fruiting plants need at least 6 hours of direct sunlight every day A. Success depends on how much sunlight plants get when leaves are out. When leaves are gone, sunlight is not nearly as important. Winter sunlight is not terribly important for trees in our climate because it is cold and the plant is dormant or “resting”. But light during spring and summer months, when leaves are out, is very important. That is when sunlight is critical. Fruit production is usually not controlled by an “on and off” switch. As the total amount of light decreases, the amount of fruit produced also decreases. At some point, if the plant does not receive enough light, flowering and fruiting stops. The amount of sunlight needed for flowering and fruiting varies somewhat among plants but fruit trees generally need a minimum of 6 hours of direct sunlight. If sunlight continues to decline during months when leaves are out, at some point, there won’t be enough light for the plant to make flowers and produce fruit. It stops producing fruit, only leaves and stems. Foliage plant, and interior plant that produces only leaves and stems, growing under very low light conditions in the Amsterdam airport men’s bathroom. This plant was selected because it requires a very low light levels to produce leaves and stems and can take a very tough conditions. If a fig tree is getting a minimum of 6 hours of sunlight when leaves are present, it will probably produce decent fruit. Not all this light has to be direct sunlight. Reflected light also counts but not as much.In direct light, light from bright reflecting surfaces, will contribute to flowering and fruit production but more indirect light is needed than direct light. Much of this depends on the total amount of light as measured in footcandles per hour or watts per square meter per hour. The quality of light, the color, is also important because it can trigger some types of behavior in plants. Fruit production also depends on the “quality” of reflected light. If light is reflected off shiny or white surfaces, then plants receive more light than light reflected from darker or variously colored surfaces.

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