-
- Articles
Index : Landscape Plants
-
-
- 23. Plants Fooled intoThinking It’s Spring - Top
- The past three weeks have been unseasonably mild with temperatures at times as much as 15 degrees above normal. Combine this with frequent rains, and you have spring-like weather that have fooled many plants into flowering and beginning to push out new growth. This is evident by plants like the yellow flowering shrub senna which are in full bloom, a full month ahead of normal. The same is true of flowering plums, peach trees, and apple trees.
Although it’s nice to have the early feeling of spring, it’s almost certain to be fleeting. We have more that a month of winter weather ahead before the ushering in of genuine spring conditions in mid-March . In fact, frost can occur here in Tucson as late as mid-March, and freezing temperatures will more than likely come again sometime this month. That means potential problems for plants that have awaken to early from their winter slumber.
When growth is activated in a plant, sap rises in the stems and dormant buds begin to swell. The first buds to open on spring blooming plants are the flower buds. They’re also the most sensitive to cold weather. So if freezing temperatures occur, the flowers die first. The un-opened flower buds are the next to be damaged. The freezing temperatures we experienced last winter caused many citrus trees to produce poorly. That’s because, even though the cold occurred before the flower buds opened, the severity of the cold (as low as 17 degrees in some locations) was enough to kill dormant buds.
With the recent unusually warm weather, citrus buds are no longer dormant and could blossom forth at any moment. But even if the blossoms aren’t fully out, any degree of freezing temperatures this month could once again kill most of the flower buds. No flower buds mean no citrus fruit this year!
Although the weather will be what it will be, there are some things that we as home gardeners can do, or not do, to avoid further encouraging plants to break dormancy to early. The first is to hold back on watering. The worst thing you can do for plants breaking dormancy prematurely is to give them lots of water. This will only speed up bud activity and hasten the development of flowers and new growth. Keep plants on a winter watering schedule. With our recent rains, I would suggest cutting back on watering even more. If you’ve been applying water to your landscape once every 14 days, then lengthen the interval between watering to 21 days. On true desert plants, cut the tap off entirely. Mesquites, Palo Verdes, Acacias, Texas Rangers, Sennas and the like have had plenty of water from our winter rains.
Do not fertilize landscape plants or fruit trees at this time of year. As new growth appears on certain plants, it may seem logical to give them some fertilizer, but as with water your only speeding up the growth that will likely be frozen before spring arrives. Given our current conditions, I would recommend delaying the normal Valentines Day fertilization of citrus to the end of February or early March. Don’t worry if this delay means you have to fertilize when the tree is in full bloom. Fertilizing will have no adverse effects on flowering or fruit set on citrus.
The only exception to cutting back on the frequency of watering and delaying fertilization to March are for winter vegetables, winter blooming annual flowers and lawns. Continue watering and fertilizing in the usual manner. Some winter blooming flowers like geraniums, impatiens and begonias can be injured by cold, but watering and fertilization will not contribute to the injury. Just protect these plants from freezing temperatures by covering them with sheets or frost cloth.
Finally, don’t prune freeze injured plants or plants that are beginning to break winter dormancy. Pruning now will speed the premature growth of plants. On freeze damaged plants, removing frozen leaves, stems and branches will only make the plant more vulnerable should freezing weather return this month. Wait until all danger of frost has past in mid March before beginning to prune off cold damaged plant parts.
Written by John Begeman, College of Agriculture and Life Sciences, the University of Arizona 520-626-5161. - Updated: February 6, 2005
-
-
[e-Mail me
the Articles] - [Search
the Articles]
-
|
