How to garden in sandy soil.

February 18, 2011

Planting a Garden in Sandy Soil

Two medical professionals asked the same question recently: what do I do to have a successful vegetable garden in sandy soil?

Sandy soils hold much less water than loam or clay type of soils.  Therefore, they need irrigated more frequently than gardens in loam soil.  Sandy soils commonly have very low organic matter.  Sandy soils hold fewer nutrients than clay or loam soils, so they usually need more added fertilizers.  Clay and organic matter in soils are the parts that hold the soil water and nutrients.  Clay and loam soils have approximately 5 times more water and nutrient holding capacity than sandy soils. 

So what can you do to have a successful garden?  Below is a list of items you may try.  You may choose to do one or a combination of the following.

1. Bring in a truckload of good loam soil and spread it over your garden area. 
1. The cost of soil is probably less than most people would expect and it is hard work to spread soil over a garden.  Once done it is there and will provide a good base for future success.  It does cost money unless you have your own source and can move it yourself.

b.      A downside is that you may bring in undesirable weed species

requiring the use of herbicides or a lot of hand weeding, the hoe hoe hoe method of weed control.

2. Add organic matter in the form of peat moss, manures, coir (a coconut husk fiber), or compost.  There are plusses and minuses of each choice.
1. This can be expensive and you need to buy quite a lot.  Spaghnum peat moss is common.  A company is now marketing compressed bricks of coir that are very uniform and will do very well.  Look on the website, Dirt Works.  Also look for Cocopeat.  Coir holds water very well.
2. There are natural nutrients that come with organic matter
3. Certain types of compost may have excessive amounts of certain nutrients.
3. Set up a method to water frequently and add supplemental fertilizers through the growing season.
1. There are good water soluble fertilizers available for a reasonable price.  Hoses and tubing can be costly and take effort to set up. 
2. The cost of water can be expensive if water comes from a city water source.
3. Over time, you may need to watch for low levels of micronutrients then add as appropriate.

The three keys to success for gardening are a soil with good fertility, adequate water and a good sunny location.  A 25 x 25 sq foot garden should only need 5 to 10 lbs of a good balanced fertilizer per year.  Fertilizers you may want are All Purpose 20-20-20 early in the season, then switch to Super Bloom just before plants bloom.  Both are available from Green Light or ask for them at your local nursery or garden center.

A sunny location would have at least 12 hours of complete sun from sunrise to sunset.  15 hours is preferable.  Water should be maintained at 50-100% field capacity during the growing season.  Field capacity is the amount of water a soil holds after all extra water has drained away.

One last item is plant quality seeds of good varieties or choose good plants from a nursery.

The Garden Doc