White asparagus, or blanched asparagus, is one of Martha's favorite vegetables to grow. The paleness of the asparagus is the result of preventing sunlight from reaching the plants as they mature. Without light, photosynthesis does not occur, and the stalks do not turn green.

One method for growing blanched asparagus is to mound dirt around each stalk, increasing the dirt pile as the plant grows. You can achieve the same results without this labor-intensive technique if you have a blanching box. A blanching box is set over a number of plants at once, keeping them in the dark as they grow.

Blanching Box How-To
Tools and Materials
4 pieces of 36-by-12-by-1-inch cedar
2 pieces of 22-by-12-by-1-inch cedar
26 one-and-a-half-inch galvanized screws
1 handle (with attaching screws not more than 3/4 inch long)
Vinyl caulk or gaffer's tape
Drill with countersink bit

Directions
1. Two of the 36-inch pieces form the long sides of the box. The 22-inch pieces form the short sides (placed between the longer pieces so that the box's dimensions are 24 by 36 inches). Attach the pieces with screws set in 3 evenly spaced, countersunk holes per joint.

2. The two remaining long boards will serve as the top of the box. Lay them across the box, lining up the edges, and drill 2 countersunk holes in each along the short ends and 3 more down each side. Screw the top pieces down to the box.

3. Center the handle on one long side of the box, parallel with the top, then attach with the accompanying screws.

4. Finally, turn the box over and either caulk or tape over the inside joints to prevent any sunlight from sneaking through.

5. Once stalks start to break the soil surface, make sure that the area around them is nice and moist, watering it if necessary. Carefully place the box over them, and mound dirt around the base to ensure that light cannot get underneath. As the weeks pass, check under the box regularly. Soon you will harvest tender, nutty blanched asparagus.