Site Selection
Selecting an appropriate vineyard site is the first of several important steps in establishing a new vineyard. Here are a few of the key factors for site selection:
Weather/Climate
It is important to have a good understanding of the climate data of the region you are looking to plant a vineyard. This is especially true when pioneering a new region to grapes. The total amount of rainfall, frost-free days and maximum and minimum temperatures are some of the factors that need to be considered. With this information, planting site and varietal suitability can be narrowed down.
Soil Profile
It is important to look at the soil type and structure when planting a vineyard. This will aid in choosing the most appropriate rootstock for the site as well as deciding the depth and frequency of tile drainage required to properly drain the field. Having this information may also show some deficiencies in the soil that should be addressed prior to planting.
The Lay of the Land
There are several issues that can be essential in selecting a planting site which are not directly related to the soil but rather in the field’s topography.
The natural slope of the field and its surroundings can play a key role in moisture drainage as well as air drainage. Both of these factors can influence the potential for disease susceptibility. Having a good natural slope also aids in preventing cold pockets and the risk of frost damage. Windbreaks such as trees or bush lines also can add to disease pressure and need to be considered.
One other factor that can cause problems and needs to be taken seriously is the surrounding crops and the practices pertaining to them. This particularly becomes an issue regarding chemical application. Chemicals used on certain crops can be detrimental to the well-being of a vineyard and vise versa.
Field History
If available, it is beneficial to have knowledge of past cropping and practices used on a specific planting site. This may make the difference of whether a field can be planted immediately or should sit fallow with a cover crop for one or more years.
Land Preparation
Land preparation is an aspect of vineyard establishment that is often neglected and can negatively affect a vineyard for many years after planting. The best-recommended procedure for land preparation involves several stages.
Tile Drainage
Tile drainage is a very important aspect of field preparation. Grapevines do not like “wet feet” and it is important to allow excess soil moisture to drain off. Excess soil moisture not only suffocates the roots and stresses the vine but it can also cause many problems for tractor work during a wet season.
Land Leveling
The importance of this step is often overlooked when preparing a vineyard site. However, many fields that appear flat have low spots, which trap soil moisture causing hot spots for disease and create pockets for potential frost damage.
Deep Ripping
Deep ripping the land prior to planting is just as important as making sure that the top soil is finely tilled. Breaking up the sub soil allows the roots on young vines to grow deep and establish themselves more rapidly. Root establishment is a key component to creating a healthy vineyard and translates to more hearty vines and higher potential for good quality yields.
When deep ripping a field it is important to rip once in the direction of the future rows and once across the rows. For example, if your rows run North to South then rip once North to South and once East to West. This will not only break the subsoil better but also allow greater ease for mechanical planting which results in straighter rows. The deeper you rip the better for the vines, but generally, the ground should be ripped between 18 – 24 inches in depth, keeping in mind the depth of the drainage tile as not to damage it. Another advantage to a deep ripped field is better field drainage due to the broken hard pan allowing earlier entry for planting.
Sod Mulching
Sod mulching can be accomplished using several tools. The most effective is probably a moldboard plow, which turns the sod over at a depth of approximately 8 inches. If a plow is not available, a good crosscut disc or mulch finisher will do as well but it is important to try to break up at least 6 inches of top soil.
Finish Tilling
All of the previous steps are best accomplished during the fall prior to planting a vineyard. This allows good drainage for spring as well as some time for the sod or cover crop to decompose adding organic matter and nutrients into the soil. As with sod mulching, several tools can be used for finish tillage.
Typically, a light disc to break up the crust is a good start, then followed by a few passes with a finish cultivator and your field should be ready. Some growers like to do one pass with a roto-tiller just prior to planting. This breaks up any remaining chunks of soil and provides ample loose soil to close any furrows or holes during the planting process.
Planting and Vine Care
This step is often taken for granted when establishing a vineyard, mostly due to the ease of mechanical planting and time constraints with other farm duties. However, there are a few aspects that should be kept in consideration before, during and after the plants have gone into the ground.
Pre-Planting Vine Preparation
In many cases, due to tight schedules and organizing planting times with a contractor, vine preparation is overlooked and in most cases, the vines do grow without any obvious problems. However when conditions are less than ideal, whether it be heavy soil conditions or a dry growing season, vines can be unnecessarily stressed causing reduced growth and ultimately taking longer to bring the vineyard into full production.
All bare rooted vines that are planted in Canada have spent the last 6-7 months in cold storage, out of the ground. During this time, vine suppliers take all the precautions possible to prevent the vines from loosing any of their moisture. However, simply by being out of the ground and handled, it is inevitable that some moisture will be lost. Hot Water Treatment also magnifies this moisture loss and, due to a recent CFIA mandate, is now mandatory for all imported vines coming from Europe. It is recommended to soak the vines in water for 24 to 48 hours prior to planting in order to replenish the vines of any moisture that may have been lost during storage and transportation. During this time, it is important that the vines are shaded and protected from wind.
Another step that can be taken to encourage the root growth of a freshly planted vine is to trim the roots just prior to putting them in the ground. Many of the vines come trimmed evenly from the nurseries but these cuts may have been made 6 to 7 months earlier at the time of grading. Making a fresh cut encourages and stimulates fresh root growth, which ultimately establishes the vine in less time bringing your vineyard into production earlier. There are differing views on how much root mass should be left after trimming. The most important point is that there is a fresh cut to stimulate the roots. The final length of roots left will be determined by several factors pertaining to the planting method used. It is best to seek the advice of your vine supplier if there are any questions.
Planting
Planting is accomplished using many methods from fully mechanical planting machines to walking through the vineyard with a shovel. One method is not necessarily better than another for the vine as long as a few simple principals are followed.
The first does not directly relate to the process of planting but can play a key role in the survival of the plant. Planting temperatures approaching 30ºC should be avoided. The temperature outside, during planting, is normally not of concern until temperatures approach 30ºC. At this point serious damage to the vines may occur due to potential melting of the wax that covers the buds. However, if vines are already planted and the forecast is predicting high temperatures there are two choices for combating the high temperatures.
You can either lightly overhead irrigate, which cools the vines by evaporation, or cover the vines with soil. If the vines are covered with soil it is important to uncover the vines before the buds start to sprout. If the vines begin to sprout underground and are then uncovered, the shoots are very susceptible to sun burn because they are not yet accustomed to direct sunlight.
When planting a vine there are a few items to conside. Assuming that the field has been prepared properly it is important to consider current field moisture levels, especially when mechanically planting the vines. Too much moisture in the ground causes difficulties in closing the furrow that is created by the planter. In many cases this will need to be followed by stomping around the vines by foot in order to ensure that there are no large air pockets left surrounding the roots. If you are questioning your field conditions, talk with your planting contractor or vine supplier. During the planting process it is important to protect the vines from the elements until they are in the ground. Basic care is to keep vines protected from wind and keep them in the shade until planting. If possible, it is good to bring the vines out to the field in the same container that they were presoaked so that they are in water up to the time of planting.
Plant depth is one of the most commonly asked about topics related to planting. It is important to create a furrow or hole that is deep enough to allow the roots to point down and not redirected upward. The hole or furrow should also be filled with loose soil to surround the roots. The size of hole does play a role on the success of the vine especially when interplanting in an existing vineyard and the soil is not pre-tilled. The more loose soil there is surrounding the roots the better. This allows the roots to establish with out difficulty. If an auger is used for planting it is best to use one no less than 8” in diameter and bore the hole deeper than necessary. This again allows the roots to grow down easily instead of trying to break through the hard walls created during boring. The final grade of the soil should be 2” below the graft union on a grafted vine or the trimmed shoot on an own rooted vine. This will allow for maximum root depth and surface drought protection while permitting for a low graft union and maximum winter protection while up hilling.
Post Planting Vine Care
Once the vines are in the ground, watering and weed control become vital. Under many normal growing conditions vines will struggle through regardless of the effort, or lack there of, put into these practices. However, with current heat treating protocols for European vines, these need to be emphasized in order to ensure best survival rates.
Weeds can create competition for nutrients, water and sunlight. The best rule to follow regarding weed control is the fewer weeds the better. Most newly planted vineyards will need to be controlled by mechanical means unless extreme caution is used to protect the vines while using chemical methods of weed control.
The administration of water has been a mystery for years. What is the best method of irrigating? When is the appropriate time to irrigate? How much water should be applied? These are all questions that have long plagued growers of all crop types.
The best methods for irrigation on a new vineyard site are trickle, drip or with a water lance. All of these methods provide greater control over water application, directing it specifically to the vines. Using these methods prevents the area surrounding the vines from receiving the same amount of water aiding in weed control. Often overhead irrigation is the only option and is better than having the vines stress due to drought. If this is the case, special care may need to be taken during certain growth stages when shoots may be susceptible to breaking off the vine. Overhead irrigation also tends to compact freshly tilled fields and may need to be tilled again as equipment reentry is possible. Due to the high amounts of moisture in overhead irrigated fields, disease pressure is also a factor that will need to be kept in mind.
When it comes to the question of when to irrigate there is no simple answer that blankets all the various soil types and drainage characteristics of each field. The biggest problem being by the time stress is evident in the vines water should have been applied.
Although there are simple tools, such as tensiometers and moisture blocks that can aid in monitoring soil moisture, the best advise is to become familiar with the soil types in your field and how they retain moisture. Freshly planted vineyards will always require water before established sites due to the root zone being closer to the surface. When dealing with vines that have been Hot Water Treated watering becomes more important due to the dehydration that occurs during the treatment process. Hot Water Treated vines will show signs of drought stress before untreated vines. A general rule is if the vines have not received any significant rainfall (0.5”-1.0”) by one week after planting then they should be watered.
The amount of water that should be applied is another question that is very site specific and is dependant on many factors in each field. This is one area to which the “more is better” philosophy does not apply. Too much water can add undue stress on vines and it is better to apply a gradual amount more frequently then to drown them in one application. If the amount is in question, it may be best to contact an irrigation consultant or your grapevine supplier for advice.