Vegetable Gardening Tips, Advice and FAQ's

Planting Small Seeds in Clay Soil

Q. Why haven't my carrot and onion seedlings come up after 2 weeks? I planted onions and Carrots in one bed - 1/2 on the front end and 1/2 on the back. Since the seeds are so tiny, I was wondering if my watering was causing them to NOT start. I have faithfully been watering this bed for 2 wks. twice a day w/o any sign of seedlings

The day-time temps range from hi's in the 90's and the night-time temps are in the 50's. We used both products. Pre-plant and (now) weekly feed. They are grown in a mix of 1/2 virgin clay soil and 1/2 peat moss. I dug down into the beds about 1 1/2 foot and then put in the bale of peat moss. I mixed in the virgin soil after that. I made a 1/2 inch furrow for the carrots and placed the seeds in that. For the onions - I just placed the seed on top of the soil. For watering, I used the end of the hose with a rag on the end and flooded the area. When the watering system was in, I used that - again flooding. The water goes away in a couple of minutes.

A. Planting carrot seed 1/2" deep in clay soil is much deeper than is wanted, and placing the onion seed on the surface leaves it vulnerable to being dried out by the direct sunlight. Also,

Soil preparation with 50% peat moss was rather costly and time consuming, and I recommend a much simpler solution.

Use no soil amendments, but use whatever soil you have as-is. Make a very shallow furrow on each side of your level soil bed next to the ridges. Mix the seed with sand in a ratio of 100 parts sand to one part seed (16 ounces sand to 1 teaspoon seed - or 1/2 kg sand to 5 grams seed). Distribute evenly in the furrows. Cover with 1/4" (3/4 cm) SAND - not clay soil. Thereafter, if your soil begins to crack as it dries out, sprinkle a few pounds or kg of sand in the planting area and water. The sand will fill the cracks and solve that problem

The soil should be kept damp but not wet. Watering clay soil twice each day by flooding could have drowned your germinating seedlings. Also, the constant moisture and high humidity greatly encourages fungus diseases, which can also kill them.

Water gently, so as to not disturb the seed, and just enough to maintain moist, but not wet soil conditions. Do not use any fertilizers, other than those you mixed with the soil in making the beds, until your seedlings have emerged - then begin feeding the weekly feed down the center of the bed, making sure they do not come in contact with the tiny plants.

Last Modified: 2004-05-02 Number of views: 2598