| [Image: High-speed straight tines for cultivator] |
| [Image: High-speed straight tines for cultivator] |
| [Image: High-speed cultivator] |
A basic sweep cultivator can do an excellent job of cultivating vegetable crops, but it must be run slowly (1-2 mph) when the crop plants are small.
A simple modification to a sweep cultivator allows high speed cultivation of small vegetable crops. The same basic cultivator can be used for an early cultivation and then converted back for more aggressive later cultivations after the crop has grown taller.
Straight Rolling Cultivator Spiders
The key to high-speed cultivation of vegetable crops is to replace the cultivator sweeps that run between or adjacent to the crop rows with straight rolling cultivators (Figures 1 & 2). These spider gangs are similar to small rotary hoe gangs. They have no twist on the ends of the tines like regular rolling cultivator tines, thus they do not throw soil to the side. They are also run straight rather than angled, completely eliminating any tendency to throw soil to the side. To fit between 10-inch twin drills, four spider wheels are mounted in tandem and staggered as shown in Figures 1 and 2. These wheels can be run close to rows of small crop plants (less than 1 inch high) with no damage to the crop. They can be run at speeds of 5 mph or more without throwing soil.
Equipment Modification
As shown in Figures 1 and 2, four spider wheels are mounted on a bracket. This bracket replaces the shank on a sweep cultivator. Only two bolts are necessary to switch components, and the gauge wheel and depth control of the cultivator gang are maintained. Cone guide wheels are used as usual. The only other modification needed is to raise the rolling cultivator gangs on the bed sides (Figure 3) temporarily since those gangs tend to throw some soil onto the bed tops. Raising the rolling cultivator gangs is easily done by removing the nut on the spring rod and inserting a 4-inch spacer cut from ¾-inch steel pipe. This configuration is capable of providing precise cultivation of vegetable crops less than 1 inch high at speeds of at least 5 mph. Since the rolling cultivator gangs on the sides of the beds have been raised, the sides of the beds will not be cultivated while the plants are small, but experience has shown that the smooth cone guide wheels actually do a pretty good job of removing small weeds on the bed sides.
When The Crop Grows Taller
Once the crop has grown a little taller, the cultivator can easily be switched back to the standard configuration by removing the straight rolling cultivator gangs and re-installing the sweeps and dropping the rolling cultivator gangs on the bed sides. This takes only a few minutes per row. Once converted back to the standard configuration, the sweep cultivator can perform precision aggressive cultivation of larger vegetable crops (4 – 6 inches high) at speeds of at least 8 mph – without damage and without the need for a skillful driver. At this point, the bed sides are cleaned and the beds are somewhat rebuilt by the rolling cultivator gangs on the bed sides.
In summary, a precision sweep cultivator can easily be converted for high-speed cultivation of very small crop plants – without crop damage – and then easily converted back for later high-speed aggressive cultivation of the plants after they grow taller.