South Jersey RC& D Council, Inc.

 

Effective Root Zone Depth

Truck Crop Effective Root Zone in Inches Truck Crop Effective Root Zone in Inches
Asparagus 24 Lima Beans 24
Beets 12 Muskmelons 24
Broccoli 12 Okra 18
Cabbage 18 Onions - bunch 6
Carrots 12 Onions - dry 12
Cauliflower 12 Parsnips 12
Celery 6 Peas 18
Chives 6 Peppers 18
Collards 18 Potatoes 18
Corn (sweet) 24 Pumpkins 24
Cucumbers 18 Radish 6
Dandelion 6 Rutabagas 12
Egg Plant 18 Shallots 12
Endive 6 Snap beans 18
Escarole 6 Spinach 6
Fennel 6 Squash 24
Horseradish 18 Sweet Potatoes 24
Kale 18 Swiss chard 12
Kohlrabi 18 Tomatoes 24
Lettuce 6 Turnips 12
    Watermelons 24

 

Field Crop and Grain Effective Root Zone in Inches Fruits, Berries and Orchards Effective Root Zone in Inches
Barley 24 Apples 24
Corn (field) 24 Blueberries 18
Millet 24 Cane fruits and grapes 24
Oats 24 Cranberries 6
Rye 24 Peaches 24
Sorghum 24 Pears 24
Soybeans 24 Strawberries 6
Wheat 24    

 

Grasses and Legumes Effective Root Zone in Inches Grasses and Legumes Effective Root Zone in Inches
Alfalfa 24 Reed canarygrass 24
Bluegrass 18 Red Clover 18
Bromegrass 24 Sudan grass 24
Ladino clover 18 Sweet clover 24
Orchardgrass 24    

 

Flowers Effective Root Zone in Inches Nursery Plants Effective Root Zone in Inches
Annual Flowers 6 Bedded plants after propagation 6
Ericaceous ornamental plants (azalea, etc.) 12 Finished landscape plants, ready for sale 18 to 24
Gladioli, peonies, iris 12 Ground cover plants (vinca, ivy) 6
Other bulb or corm plants 12 Lining-out plants 12
    Perennial ornamentals - trees and shrubs 24
 
Turf Effective Root Zone in Inches Turf Effective Root Zone in Inches
Athletic fields - in active use 6 Athletic fields - not in active use 12
Golf greens (bentgrass) 6 Golf fairways (bluegrass, fescue, zoysia, Bermuda grass) 6
Grass sod - being established or being prepared for immediate sale 6 Grass sod (lawns, sod being held for sale) 12

 

Each crop was given a depth based on:

  1. Depth of soil to which the larger proportion of the total root system has developed when the marketable part of the crop is being produced or when the loss of water from turf and ornamental plants is greatest.
  2. Research and experience regarding the overall water needs of each crop for maximum quality as well as yield or growth.
  3. The kind of soil in which some crops, such as blueberries, Bermuda grass, and sweet potatoes, are commonly grown in New Jersey.

Depth of irrigation while the crop is developing its root system should be determined by the actual depth to which roots have grown.