How close to oak trees can you add rock hardscaping to reduce lawn space and water?
I’m sure that you are not alone in wanting to reduce some lawn area so that you can reduce irrigation and mowing, but when removing turf and replacing with hardscaping around trees, you should be very careful. First, you want to leave some space around the trunk, about 2 feet on each side should be sufficient, and use bark mulch in that area, if possible. You want to limit soil compaction over the larger roots of an older tree. When removing the turf, be very careful not to damage any of the tree roots, which are hopefully deeper in the soil. Using rocks as mulch around the tree is fine, since there is space between the rocks for water and air to penetrate the soil. But be careful if using pavers or other hardscaping around a tree. You can use pebbles or sand between the pavers, which would allow for some water and air to work their way into the soil, but not as much as rocks or other mulch. So the soil underneath pavers will become more compacted and when the roots grow, the pavers will buckle and be unattractive and are also a potential tripping hazard. The smaller roots, which have root hairs, occur out at the dripline of the tree, at and beyond the furthest branches, are where the tree takes up water, so you want to be sure that any construction that you do leaves this area permeable for air and water to get down to the root zone.
Can plants actually sun scald?
And the answer is yes, they can. The sun can damage plants in several ways; the most obvious is when you see actual brown, burned spots on the leaves. The intense heat of the sun simply bakes the leaf tissue, killing it. You may also see sun scald on the fruit of peppers and tomatoes, if the fruit is exposed to the intense light of the late afternoon sun. Another common sun injury is on the southwest side of the trunk of young trees. When trees are young, their bark is not very thick and can be easily damaged by the intense rays of the sun. The bad news is there’s nothing to be done for sun scald once it’s occurred. Dead plant tissue cannot be repaired. But the good news is, sun scald can easily be avoided. First, you should know whether or not your plant can take full sun. The label that accompanied the plant when you bought it may or may not be correct on this issue, so do a little extra research. Also, even plants that can take the full sun need to be acclimated to it if they haven’t ever experienced it. A plant that has been on your porch for several weeks, out of the direct sun, will no longer be able to handle those bright rays, so start by moving the plant into the full sun for a few hours in the morning, slowly lengthening the time to all day before you actually put it in the ground.
Is mulch safe to use in a garden bed that has been stored outside and now has mold growing in the bag?
You should separate out the moldy portion and toss it in your compost pile, and the rest is safe to use. The moist environment in the bag with all that yummy, dead organic matter is the perfect place for mold and other fungal spores to take root. You don’t want to use the moldy mulch in your garden, simply because it would serve as a source of spores for the colony to spread. But the mold is feeding on dead tissue, not living, so unless the bed was kept far too wet, the mold wouldn’t damage your plants. In fact, there are dormant mold spores just about everywhere, just waiting for the situation to be right, so they can germinate and grow. But take away the environmental problems, such as too much moisture, and the colony will quickly die out. Soil is actually teeming with many different species of microbes, most of which pose no threat to normal plant life, and even help improve it by breaking down dead organic matter and converting it to life-giving nutrients. So when you toss the moldy mulch into your compost pile, other microbes get involved in the process and continue the job of breaking those wood chips down into smaller and smaller pieces, until you have rich, humic compost to add back to your soil. So, if you find that the mold is wide-spread throughout the bag of mulch, or if you just want to err on the side of caution, you could simply empty the whole bag into your compost pile, and let nature run its course.
We know it’s too hot and dry to plant right now, but if we must, or if we’re starting a fall vegetable garden, how do we best protect our new plantings?
Although some plants, like lantana, okra, bird of paradise, and other truly heat-loving tough guys will not bat an eye if you plant them in mid-summer in Texas, most plants will struggle. The sun here is just brutal. But sometimes it’s necessary to plant in summer, and the good news is that you can help your plants transition. It’ll take a little bit of effort, but will be well worth it. All you need to do is build a simple, even crude shade structure for them, to keep out some of our burning sunlight. A very easy way to do this is with PVC pipe and shade cloth, both of which are easy to find at home improvement stores and most nurseries. PVC pipe is relatively easy to cut with a small hand saw, and you can build an A frame and just drape a large piece of shade cloth over the top. To build a larger shade frame, you can use thin wooden stakes, which can be hammered into the ground relatively easily, and use a staple gun to staple the shade cloth onto them. Shade cloth comes in different weights, keeping various amounts of light out. About 30% sun blockage should do the trick. Make sure that there is plenty of air circulation under the shade structure around your plants. If you’re protecting a vegetable garden, you may choose to leave the shade on until daytime temperatures fall back down into the 80’s. Although vegetables can handle more light and you can remove it earlier, once they’re established, the plants will be less stressed in a bit of shade. Although too much shade will inhibit their ability to fruit, so don’t overdo it. If you’re simply protecting a landscape plant, such as a perennial with delicate leaves, a few weeks under a bit of shade should do it. Any rudimentary shade structure will do the trick, so don’t think you need to get too fancy. But make sure that the wind isn’t going to pick it up and blow it away.
Jimsonweed, Datura wrightii, also known as moonflower or angel trumpet
This lovey plant has large, gorgeous trumpet-shaped white flowers that open at night. The most common way to get this plant is by having a friend share some seed with you. Once the flower has been pollinated, a very large, spiky seed head forms, containing hundreds of seeds. If you don’t collect those seed heads before they burst, you’ll find lots of Datura seedlings coming up all over the place next year, although the plant really isn’t invasive and the seedlings shouldn’t escape too far. Datura is listed as hardy to zone 9 and so it may be perennial in your garden. But most likely it will reestablish from seed, so be sure to collect and save some so that you can plant them where you want them next year, and give some to jealous friends. Datura only gets about 2 feet tall, but may spread very wide, up to 10 feet, especially if it’s getting plenty of water. It doesn’t need much water at all and prefers well-drained, coarse soil, but if given a little supplemental irrigation, it will get a bit larger and flower more prolifically. Datura needs full sun to grow and produce those gorgeous white blooms, which usually start to show in late May or early June and cover the plant all summer long. Be very careful when handling this plant. All parts of it are poisonous if ingested and some people are allergic and have a reaction when touching its fuzzy gray-green foliage. Datura is a great plant for xeriscaped areas in your garden, and requires very little care or attention to be beautiful all summer long, even in the extreme heat.
Ruby crystals grass, Melinis nerviglumis ‘Pink Crystals’
My friend Jenny first introduced me to this lovely little ornamental grass, which makes a wonderful addition to very dry areas the landscape, especially in xeric gardens with decomposed granite beds. It stays small, getting only about 18 to 24 inches tall and a little less wide. The delicate, light green foliage clumps from a single base, the same as other ornamental grasses. But the real show-stopper on this plant is the rosy pink, softly textured seed heads that sway gently in the breeze. Ruby crystals grass prefers the full, intense sun, takes very little water, even during establishment, and looks great from spring all the way through summer. The seed heads detach and blow away once they’ve dried, and the plant reseeds easily around the garden, so keep an eye out for it in areas where you might not want it to grow and simply pull the seedlings before they get very big.
Okra thrives in the heat and is actually quite beautiful, so consider using it as a specimen plant in the landscape. Like most of our warm-season vegetables, okra may be planted as both a spring and fall crop. But “fall” here doesn’t equate to what most of us think of as fall. Here in Central Texas, we must plant our “fall” gardens in late July or August, since you’ll need to plant in summer in order to reap a HARVEST in the fall. There are many great cultivars of okra to choose from, but one of my favorites is ‘Burgundy’, which, as its name implies, has deep burgundy fruits, and even quite a bit of burgundy color in the leaves and stems. Okra requires full sun and minimal, and will do just fine with very little supplemental irrigation, but if you water at least once a week, you’ll get a lot better harvest. An area with well-drained soil is best, and if you’re preparing a new area, it’s a good idea to incorporate about an inch of compost to the bed. As the compost breaks down over time, it improves the structure of the soil, and adds a small amount of nutrients slowly. Okra will also benefit from a little fertilizer, which you can add after the first harvest to ensure that the plant has plenty of nutrients to produce more fruit. Okra plants get very tall, so they need plenty of soil depth to anchor themselves. In shallow, rocky soils, they may fall over. Give each plant about a foot on each side to fill in. This fairly narrow width and taller height make okra a nice addition to a spot where you may have had winter annuals that have now died-back.
Portulaca and Aptenia, both of which are commonly called “ice plants”
Using the common name for plants can often lead to confusion, and with the common name “ice plant,” this seems to be especially true, as most any succulent plant that spreads along the ground, thrives in the heat, grows in rocky soil, and has strikingly beautiful leaves is called ice plant! Most ice plants will do very well here in Central Texas, especially in the summer. But some species don’t tolerate our cold winters. So be sure to do your research before you plant. Aptenia is also known as “hearts and flowers” and as “red apple plant.” Both it and Portulaca are very easily grown: Portulaca from seed and Aptenia from cuttings. In fact, if you have a neighbor with Aptenia, ask them if you can break a piece off. Take it home and let it air dry for about an hour, so that the broken surface heals a bit, then put it directly into your landscape and water just a bit: the ground will be covered in no time.