A Blessing And A Curse: Sand As Far As The Eye Can See

As gardeners on the eastern end of Long Island, we are both blessed and cursed.

We are blessed with a growing season that, for the Northeast, is long and mild. But then there is the wind and the salt.

Though we often get off to a slow start, we get more sun and more days to garden and grow our plants than any other place in the state. Our maritime climate allows us to grow a range of plants not dissimilar to those you may find in London.

While there are spots like the Pine Barrens, where winter temperatures can often fall well below zero, the length and depth of the cold always seems to be short. Most plants will tolerate short periods of extreme cold; it’s the prolonged and deep cold that we seem to be able to avoid as our surrounding waters temper even the bitterest times of winter. We can often grow well into the fall with hard freezes and frosts on the South Fork often holding back until mid-to-late December.

But for the downside; closer to the ocean and bays, the wind and the salt tend to create limits on what we can grow and how tall. And of course there are the occasional hurricanes, which are akin to Mother Nature’s pruner and chain saw.

The most limiting factor, though, is the curse that confounds gardeners, yet is the single element that has drawn most of us out here: the sand.

You may have noticed that it’s tough growing things in sand. Some plants have adapted. They often are succulent with the ability to store moisture, or have tomentose (grey and hairy) foliage that catches every drop of dew and percentage of humidity. Those you commonly see out here are the low bush blueberry, pitch pine, scrub oak, beach artimesia, beach plum, beach pea, yucca and the prickly pear cactus.

There are, however, strategies for dealing with the sand that can allow you to grow just about anything. But as we have learned from our careless mistakes, thoughtfulness and common sense must play a big part in our plans.

We were not very thoughtful 30 years ago when potato farmers used Temik, which was applied to the soil, then absorbed by the potato plants, making them toxic to the potato beetle. It worked great for a while but then it began showing up in our drinking water. You may have noticed that sand is kind of porous. And yes, the Temik just leached right down to the water table. The same thing happens with other garden chemicals, road salt, fertilizers and what goes into our cesspools.

But when you add a few seemingly magical ingredients to this sandy soil—like loam, compost and other organic matter—the leaching is slowed and a physical bonding takes place that allows you and me to grow our annuals, perennials, trees and shrubs. It’s really rather simple and so totally organic. The grapes seem to love it. The potatoes used to thrive in it and there are more than a few commercial nurseries and sod farms that have made the soils of eastern Long Island their home for decades and decades.

So, you may be new to the area or you’ve been here for a while and have found growing in our sandy soil too much of a challenge. What can you do?

There are two solutions. You can choose one, or you can mix and match. For large scale projects you need to amend the sand, that is, add organic matter en masse. For smaller projects, you move above the sand and do your growing in raised beds, planters or pots.

Adding organic matter to sandy soil does a number of things. The addition of loam or compost allows the newly created soil to absorb water and nutrients, the building blocks for plant life.

But there is more that our plants need. There are bazillions of micro-organisms in soil that make it alive. They break down the organic matter, making it available to the plant roots, creating chemical and biological reactions. And the larger organisms, like soil-borne insects and worms, keep the mix aerated and in motion.

There was once a time when our solution to sandy soil was to find a landscaper or farmer who would sell us their topsoil. It wasn’t uncommon to have truckloads of farm topsoil delivered to your garden or new home for as little as $15 a cubic yard. Bluegrass lawns were laid on farm-harvested topsoil and properties on which Hamptons mansions sat were landscaped edge to edge with local farm topsoil. Not any longer.

Topsoil is now considered a natural resource that’s actually regulated in many communities and can’t be moved off site for sale or use in other areas. You should always be suspect when you’re offered topsoil by the truckload and inquire what the source is and how it happens to be for sale. Many times it’s actually manufactured and not topsoil at all.

On the other hand, you can buy high quality composts that are made locally or trucked in. Again, ask what the sources of these composts are and how they’re made. Some may even be certified and tested for content and quality.

These composts can be added to sandy soil to create sandy loam. And when worked into the sand to a depth of 6 to 10 inches or more, an organic layer can be created that will support a wide range of plantings—from annuals to perennials and vegetables to shade and fruit trees and shrubs.

For vegetable growing in sandy soil, the best strategy is probably to use raised beds. These raised beds can be simply made from kits or store bought lumber (be sure to avoid lumber with wood preservatives) and can be elaborate or as simple as 4-by-4-foot or larger squares set on top of the sand and filled with garden soil.

Raised beds have a number of advantages, including ease of access, earlier harvests and better control of moisture, weeds and insects. They need not be limited to wood frames though, as stone is often used as well as other materials. Keep in mind, though, that the soil in these beds will need occasional rejuvenation by adding composts on a regular basis.

For direct planting into sandy soils, we usually add amendments such as compost and manures to add the necessary organic content that will support life and growth. This can be done in creating a planting bed for projects such as roses or a perennial border or for individual planting holes for trees and shrubs.

Whatever method you use to garden in sand, remember a few things. Sandy soil is like a sieve to chemical fertilizers and pesticides. Organic fertilizers are better, but even in a sandy soil without organic matter these too can leach and create problems.

The solution: compost, compost, compost. This cuts down your waste stream, provides you with an ongoing source of garden loam and it’s easy to do. And mulch. A good organic mulch slowly breaks down, adding organic matter to sandy soils. Mulch keeps moisture in the soil and it keeps the soil cool in the summer. And lastly, garden with natives and plants that adapt to sandy soils. This includes both ornamentals and edibles.

If you want to go natural and limit your need for soil amendments, concentrate on plants that thrive in sandy soils. Simply Google “plants for sandy soils” and begin your journey. Or drop me a note for some tips and links. Keep growing.