Growing Strawberries in the Southeast

Growing Strawberries in the Southeast:  

Frequently Asked Questions

Are Strawberries annuals or perennials?

The individual strawberry plant is a short-term perennial.  A mother plant can survive for several years and her growth habit will eventually contribute to her decline, but not before she creates dozens of daughters to take her place.  Since all the growth of a strawberry plant originates from the crown and the crown is actually a woody stem with very short internodes, each year the mother plant lives, the crown migrates upward.  This will eventually put the crown too high above the soil line and susceptible to winter injury and summer dehydration.  If you keep your strawberry plants for several years, you’ll notice that the original mother plants you set out will eventually die off, and the daughters will carry on the patch from year to year.

What is a ‘Strawberry Runner’?

Strawberries have their year planned out very precisely, and they use their time wisely.  When the days are long, above 13.5 hours sunlight per day, strawberries generate runners or daughters which are new plants that emerge from the mother plant.  Runners are botanically ‘stolons’, or above-ground stems that are able to root at each node and create new plants at the end of the stolon.  For strawberries, these are the daughter plants and each mother plant has the ability to generate many daughters per season.  It is important to know about this habit of strawberries so you can predict when the plants will be behaving this way and know what you want to do about it.  It can be viewed as either a resource to be captured (free new plants!!) or a pest that creates plantings that are too dense to be productive if left unchecked (“the strawberry weed”).

In the NC Piedmont, this time period of 13.5+ hours of daylight and above is the first week of May to the first week of August.  You could expect to start seeing runners form on your plants within this window of time.  After August, the plants start focusing on other things….  Below is a link to a chart of how many hours of daylight we get here in Pittsboro, NC throughout the year.

http://aa.usno.navy.mil/cgi-bin/aa_durtablew.pl?form=1&year=2015&task=-1&state=NC&place=pittsboro

How should I fertilize my strawberries?

 Strawberries appreciate a dose of compost and/or composted manure mixed into their bed before planting.  Additionally, when incorporating any compost or aged manure, add 3-4# of 10-10-10 at the same time.  If you want to use an organic fertilizer, we also carry Harmony (5-4-3) and 6-10# per 100 foot bed would do nicely.  Amending upon planting so the berries have everything they need from the get-go is the best strategy and from there, the berries will do the rest!

Planting Strawberries:  Planning and Management

As with most crops, how you plant them depends on how you intend to manage them.  Generally, you should allow at least 12” between/around each plant.  If you plant closer than 12”, the plants will crowd each other for sunlight and air flow which will negatively impact fruit production.  The bigger question is:   Are you going to treat the strawberries as annuals or perennials?  You can see by the ‘To Do’ list below, that treating strawberries as perennials creates more of a work load than treating them as annuals; choose your own adventure.

Growing Strawberries as ANNUALS:

You’ll plant in September and yank them out in June of the following year after they’re done with berry production.  Done.  Put the space into cover crop or prepare for your next crop.

• Spacing Between Plants in-row:  12”
• Spacing Between Rows in a bed:  12”
• Stagger rows to achieve better plant spacing and air flow

Growing Strawberries as PERENNIALS:

You’ll plant in September, harvest the following June then RENOVATE several months later in September for the next year of production.  The sooner you can get to this task, the better; the plants you select for the next year will benefit from having their neighboring competitors evicted and freeing up all soil, light, and water resources for themselves!

• Spacing Between Plant in-row:  12” – 16”
• Spacing Between Rows in a bed:  12” – 16”
• Stagger rows like above for initial planting
• TO RENOVATE:   (you may use a roto-tiller for some of the broad strokes)

Let the strawberries finish up with their runnering for the season, then get in there!  This could happen throughout the fall, but the sooner you clean up the space, the more time the remaining plants will have to get established for the next year of production.
Be ruthless; prepare to remove a lot of plants.  Mother plants can produce 10-20 daughters per plant, so you’ll probably be removing about 8-16 runners for every runner you keep.

• Remove… any plants that are in your aisles or on the shoulders of beds.
• Remove… all plants that are in the centers of the beds.
• Remove… all of the weakest &/or smallest runners.
• Remove… any plants that appear to be diseased.

Do you have any left?  You certainly will!  Of the remaining plants, choose the healthiest, largest plants in a 12” x 12” grid (minimum spacing_ a little more space is ok, too) and remove all other plants that are outside of that grid.

How should I plant my strawberries? 

Strawberry leaves, flowers and roots grow from a crown that should be located at soil level.  If you plant too deep, you’ll smother the crown, exposing it to wet and humid conditions that will encourage rot.  If you plant too shallow, you’ll expose the crown and roots to extreme cold in the winter and excessive drying in the spring and summer; both could kill the plant.  The ideal plant depth is to have the crown level with the soil.  Be sure to firmly compress the soil when planting so that the soil doesn’t bury the plants after your water them.  Avoid applying mulch right up next to the crown for the same reason.

What can I expect from each variety?

• Chandler – MID-SEASON - Top seller with u-pick growers; fast growing plant with high yield.  Berries have good color & flavor, medium to large size, medium firmness and a classic shape.
• Sweet Charlie – EARLY-SEASON - Plants are vigorous and bear fruit 7-10 days earlier than Chandler.  Berries are very sweet, firm & large.  Easier to harvest because of large fruit size.  Resistant to Crown Rot & Powdery Mildew; Susceptible to Leaf Blight.
• Camarosa – Plants have excellent early, mid, and late season production.  Fruit is large, conical-shaped, and sweet with a longer shelf life.  Good for fresh eating or processing.
• Festival – Plants have excellent early, mid, and late season production.  This berry is firm, mostly large, conical-shaped, and excellent in maintaining attractiveness and flavor during and after long shipments.  Most common strawberry grown in GA and FL.

Should I plant strawberries on flat ground or in raised beds?

Your soil type and your planting site will make some of these decisions for you.  Recommendations will vary based on the geographical location from which the recommendation is based, so always use your own judgment and knowledge of your own farm/garden to make the best decision for your plot.

CLAY soils will hold water very well, and in the winter and early spring, maybe too well.  Water-logging and lack of drainage during this time of year in clay soils can be very problematic and lead to plant damage, disease and decay.  In CLAY soils, it’s recommended to plant in raised beds that are between 6”-12” above your aisles to provide adequate drainage and to increase soil-warming in the spring.  The convenience of harvesting out of a raised bed is not to be underestimated, either. 

SANDY soils will drain very well & it may be difficult to keep your plants sufficiently hydrated in the spring when the plant’s water demands are highest.  In this situation, it may be wise to plant directly into flat ground or only very shallow rows (less than 6” high) to best conserve your water.

Can I keep my strawberries for propagation stock from year to year?

Theoretically, sure; realistically, it’s not recommended… Here’s why…

Since strawberries are perennials, the potential to keep them from year to year is there.  The reality of growing strawberries, however, is they are very susceptible to a host of diseases that can accumulate within the strawberry plant or within the soil over time.  Since all plants of a specific variety are genetically identical, that means all plants are equally susceptible to the same diseases and once a disease is present, all plants are at risk of becoming infected.  Once a plant is infected with a disease, it does not recover and if it is not removed and destroyed, it has the potential to spread the disease to other plants through various channels including soil, water or insect feeding. 

Diseases will make themselves known in various ways.  Some diseases will be dramatic and cause plant decay and death; other diseases will be visible as spots on the leaves; others may not be showy but rather manifest in gradual plant decline, lack of vigor and reduction in fruit production from year to year.  Beyond effecting fruit production, some diseases are soil-borne and have the potential to remain in the soil for 10+ years which means you would not be able to grow strawberries in that space for at least that much time (worst-case scenario).  For these reasons, it is recommended to purchase disease-free plants every year (or two) to ensure that plants are healthy, vigorous, disease cycles are being broken and to allow you to rotate your plants to different areas of your garden/farm and NOT transmit diseases or pests through infected plant material or soil.

Secondly, WHY do you want to keep your strawberries for more than a season?  If you don’t’ want to maintain the strawberry patch through the summer, DON’T!  Summer is the hottest, busiest, weediest time of year in the garden so get those tired strawberry plants out of there!  The space can be sown with a cover crop instead that will compete with weeds and require less of your time and attention.

Why do we plant strawberries in the fall?

Strawberries are quite possibly the only fruit that can be treated as an annual and produce fruit in under a year if you understand its physiology.  Strawberries are day-length sensitive and behave differently in each season based on how many hours of sunlight they receive.  When days are long, more than 13.5 hours, strawberries invest their energy into producing runners or daughters; this is their summer time activity.  As days grow shorter in the late summer and fall, less than 13.5 hours of day light, strawberries shift gears and focus on root development and producing floral initials, or the primordial flower buds that will emerge next spring.  You cannot see that the plant is doing this, but if you wait too late to plant in the fall or plant in the spring, you’ll notice a dramatic reduction in fruit production due to the plant’s inability to perform this function to its fullest potential.  Planting in the month of September will allow the plants to get established and set their next-season’s fruit before winter shuts things down for the year. 

What yield can I expect?

 A very general expectation is 1# of fruit per plant per season.  Various factors, that you may or may not be able to control, can increase or decrease this yield. 

These factors include:

• Soil pH and available nutrients - Test garden soil regularly/annually to make sure you’re where you need to be for the crops you’re growing.  Get soil test boxes and sample forms from your local Cooperative Extension office; send samples to the soil test lab’s physical address in Raleigh and you should have a report in 2-4 weeks.  Soil testing is FREE April-November; $4.00 per sample December-March.  We can help you interpret your results at Country Farm & Home if you need a hand deciphering  the report.
• Soil health - Always give back to your soils by adding regular and varied sources of ORGANIC MATTER.  These infusions will keep your microbial populations healthy, active and supplied with food which, in turn, ensure that the mineral nutrients that you add or that are  already in the soil will be metabolized so your plants will have access to all they need.
• Water management - Too much or too little at critical points in the growing season
• Temperature - Some years are better than others….
• Late frosts - OPEN BLOSSOMS are the most vulnerable to frosts and freezes.  Plants can tolerate the cold but the blossoms cannot.  If a late frost is expected, consider covering plants with old sheets or row coverto prevent fruit damage/loss.  Sometimes, this cannot be avoided and you will generally not lose all your fruit, just the ones that are blooming that night…
• Pests - Deer, birds, rabbits, slugs etc. are all fans of strawberries.  Plan accordingly.

How should I mulch my strawberries?

Regardless of your planting strategy, you’ll want a layer of mulch (organic, fabric or plastic) for the active harvest season to keep the berries clean, dry and off the ground.  Mulching Strawberries upon plant installation is highly recommended to control weeds, conserve soil moisture and so it’s in place when you need it as the plants and berries grow throughout the season.

Mulch Options:

• STRAW!!  No folks, Straw-Berry is not just a clever name.  Back in the day, especially in Northern growing regions before the dawn of Industrial Agriculture, strawberries were over-wintered with a thick protective layer of straw over-top of the plants to carry them through winter.  In the spring, the straw was raked away from the plants to become their mulch for the growing and harvest season.  This is still a great strategy for growing strawberries today.  In the Southeast, avoid mulching too heavily; our winters can be quite warm and strawberries don’t need quite as much protection as northern-grown berries.  2”-4” of loose straw should do the trick.  Rake mulch away from plants in March when they wake up and start growing to provide a nest for the berries that are on the way.
• Leaf Mulch - Freshly fallen leaves like Pin Oak that are slender, small and stack well to form a thick layer of mulch are great.  Otherwise, leaves make great mulch if they have been composted or run through a chipper/shredder to reduce their size.  Fresh leaves are okay, but tend to be too fluffy right off the tree to give you a lasting layer of mulch that won’t blow away in the winter.  If you do choose leaves, consider putting down a layer or two of newsprint to add another layer of weed suppression.  Over-head watering of your mulched berries will help settle everything in and ‘glue’ it in place and is recommended.  DO NOT use Black Walnut Leaves (or BW wood chips)!  They will inhibit the growth of most garden plants.
• Bark Mulch - If you have a source of well-degraded (at least a year), finely-textured bark mulch, this could be a good mulch for strawberries.  It’s recommended to lay a layer or two of newsprint down and then cover with mulch to create the best weed barrier.  Do not use fresh wood chips; they will rob the plants of nitrogen as they break down.
• Landscape Fabric/Ground Cover, woven - Many small-scale growers favor black woven landscape fabric for growing strawberries; with a tool like this, you can literally roll out your mulch onto a prepared bed (with drip tape in place) and plant directly into the fabric. 

          Order of Operations with this method:

1. Fully prepare strawberry bed INCLUDING soil amendment & incorporation, final bed-building/raking, (OPTIONAL) dig trench in aisles with which to bury the edges of the landscape fabric to hold it in place, lay drip tape (if you will not be hand-watering plants).
2. In another unplanted, flat area like a lawn or empty bed next to the berry patch, roll out the landscape fabric and tack down with rocks or landscape pins.  Use a propane hand torch to burn your planting holes into the fabric at your preferred spacing.  Start by holding the torch at least 24” above where you want the planting hole, and gradually lower the torch to the fabric until you see the fabric start to curl and melt.  Use a circular motion to achieve a round hole without warping the fabric (you’ll get the hang of it quickly).  Singe the ends of the fabric to prevent fraying over time.  Another way to make your planting holes is to cut holes with a utility knife; you can expect the fabric to fray with this method.  Roll up your fabric and take it to the strawberry bed(s).
3. Unroll your fabric and EITHER use soil to cover the edges to secure the fabric in place OR use landscape pins/staples along the edges of the fabric to hold it down.  If you use soil, cover the entire perimeter of fabric on all sides with a couple inches of soil.  If you use landscape staples, use a staple every 8’ or so around the entire perimeter to hold it in place.
4. Now you’re ready to plant!  Drop your plugs next to the holes you cut/burned and plant as you would if the fabric was not there.  After you set each plant, pull the drip tape close to the plug to ensure it will be watered well going forward.  After planting the whole bed, turn on the drip tape and water in well.

• Plastic - Pick-your-own operations in NC nearly all use black plastic for strawberry production.  Typically, this production method requires a special mulch laying implement that can build the bed, lay the drip tape, roll out the plastic and bury the edges of the plastic all in one pass.  Plastic is single-use and needs to be disposed of at the end of the season.  For these reasons, smaller growers and home gardeners generally do not use plastic.