Perry Laboratory
Nurseries
Advising and Testing for Nurseries
In nursery production, the most intensive horticulture is practiced to grow plants for all or part of them, generally for sale. The use of laboratory testing helps in making the best management decisions.
Many nurseries utilize routine laboratory testing to help track how their fertility levels are reacting to the management at the nursery. Routine regular testing gives an indication of whether the soil acidity is increasing or decreasing. The concentration of soluble salts can help determine whether the irrigation practices are providing sufficient leaching to avoid an excessive accumulation of soluble salts. Routine soil testing helps determine if the fertility levels are satisfactory for the crops being grown. This in turn reveals if the fertilizer program is operating properly. A fertilizer program entails the proper fertilizer materials being used at the correct rate of application in a uniform manner. These areas are addressed in a routine testing program. When plants are in a deficient or excessive growing system, they are often affected, however do not show the symptoms immediately. When the problem is identified early enough, it can be corrected and the symptoms may not show in the plants. Problems can occur from many areas, including the use of wrong fertilizer materials, equipment failure or personnel mistakes.
For container nurseries, generally it is best to monitor the fertility and physical properties of the potting media that the plants are grown in. This testing monitors the consistency of the mix components, along with the uniformity of the mixing process. This data becomes the “baseline” levels that the plants will initially grow in. From this point, the routine testing will follow the effects of the cultural management practices to determine if adjustments should be made. This is particularly important for Holiday crops that are grown to be ready for sale at a set date or period, where there will be less time for adjustments to be implemented.
Irrigation water testing is also very important for nursery production. The raw irrigation water may require treatment, such as acidification, in order to provide the best water for irrigating the crops being grown. Testing of the fertilizer solutions used at the nursery determines if the fertilizer materials are correct and being measured accurately and dispensed at the proper rates.
The use of plant tissue analysis determines the actual nutrient levels within the plants and can indicate possible imbalances with nutrients in the media and also the growth activity of the root system of the plants. This information can help in determining if there may be problems in nutrient uptake, unavailability of nutrients or possibly environmental problems.
Guidelines for Tissue Sampling in Various Crops
| Crop | Number of Leaves | Plant Part (leaf) | Time of Year |
|---|---|---|---|
| Roses | 25-30 | Uppermost five-leaflet from a flowering shoot just showing color. | None specified |
| Carnations | 30-50 | 5th and 6th pairs from non-flowering shoots. | None specified |
| Chrysanthemums | 25 | 4th leaf from tip | Bud start to finish |
| Alstroemeria | 20 | First fully developed | None specified |
| Azaleas | 50 | Most recently matured | None specified |
| Gypsophila | 50 | Most recently fully developed | None specified |
| Cyclamen | 15 | Top | 50 days after transplant |
| Gardenias | 25 | Most recently matured | None specified |
| Geraniums | 15 | Most recently matured | None specified |
| Gerbera | 15 | Most recently matured | None specified |
| Hydrangeas | 15 | Most recently matured | None specified |
| Kalanchoe | 15 | 4th leaf from tip | None specified |
| Lily, Easter | 15 | Most recently matured | None specified |
| Poinsettias | 15 | Most recently matured | None specified |
| Snapdragons | 25 | Most recently matured | None specified |
| Crop | Number of Leaves | Plant Part (leaf) | Time of Year |
|---|---|---|---|
| Apples | 50 | Mid shoot current growth | Mid-season |
| Apricots | 50 | Mid shoot of current growth | Mid-season |
| Avocado | 50 | Most recently fully expanded non-fruiting terminals | Leaves 5-7 months old |
| Cherry, sweet | 50 | Midshoot current growth | July-August |
| Grapes, wine | 30-50 | Petioles opposite basal cluster | Full bloom |
| Olive | 50 | Mature leaves from middle of non-bearing, current season shoot | Late June through early August |
| Peach | 25 | Leaves from midshoot current seasons growth flower clusters | Mid-summer |
| Pear | 50 | Leaves from midshoot current growth | Mid-summer |
| Raspberries | 50 | Most recently matured leaves | Flower bud start |
| Strawberries | 25 | Leaves and petioles, most recently matured | At flowering |
| Conifers | 25 | 2-3” terminal cuttings | Summer |
