Growing in the Ground

Commitment on Your Part: Your ginger seeds/plants must consistently be in 70 degrees or higher (ideally 75 degrees).  The soil temp must be 55-60 degrees or higher.  This means your plant will need to be in your house or heated greenhouse when it is cooler than 70 degrees outside.  Unless you have Hawaii-type weather (which is around 70-85 during the day and 60-75 at night), this commitment must be kept to have an optimal growing experience.

Cutting Seed (If we do not cut seed pieces for you.):  When cutting your ginger for seed, cut at the narrow parts.   The object is to minimize the surface area where you have cut.  Try to have 2 to 3 eyes on one piece.  The seed pieces need to dry out or cure for anywhere between 3 to 5 days before planting or pre-sprouting.

General Information:
Temperature:  If you live in a warm temperate climate of a consistent 70 degrees or warmer, and soil temp of 55-60 degrees or warmer; ginger can be grown outside.   Most people on the mainland do not have these temperatures consistently.   Many mainlanders have found it helpful to grow in hoop houses.  If you plant the ginger in the ground, buy clean seed from Paradise Pure each year because ginger can easily pick up a disease from the soil (i.e. bacterial wilt)

​Water:  Ginger likes the growing medium to be evenly moist (not soggy), and more in the heat of the day.  Make sure your growing medium/soil has good drainage.

​Sunlight:  Ginger likes indirect light especially in the first few months.

​Pre-Sprouting: (optional):  Pre-sprouting gives your ginger a jumpstart on the growing season while you are waiting for temperatures to increase outside.  In the meantime, place the seed flat (about an inch apart) in flat nursery trays on top of 1/2” of good quality growing medium. .   A mixture of sphagnum moss, coconut coir, and perlite make a nice growing medium.  Also, add slow-release fertilizer (example would be 4-6-4 Sustane) and an inoculant at this time.   Cover the ginger lightly with the medium; it is okay if tips of your ginger protrude a little out of the medium.  Keep the ginger evenly moist; do not over water.   During pre-sprout, keep your temperature 70 degrees and warmer day and night.  In approximate 2-3 weeks, sprouts will pop up through the medium.   Wait until your plant is about 7” tall before you put them in the ground. 

A Note About Beneficial Microorganisms (in other words, an inoculant):
An inoculant is an organic soil amendment that provides a broad spectrum of beneficial microorganisms, enzymes, vitamins, and various organic acids. Healthy soils require organic matter, like compost, microbes, and moisture that supports a healthy environment for plants. The result is strong plants and healthier flowers and higher quality fruits and vegetables.  Healthy plants are better able to resist diseases and pests.  These are all essential components for healthy soil and plants.   Inoculants come in liquid or dry.

How to Plant Ginger in the Ground
Ginger is a heavy feeder and it is important to give it enough fertilizer.   Do not scrimp on fertilizer.   A reasonably balanced fertilizer needs to be available close to the root zone.   Pelleted composted chicken manure (5-5-5) is usually sufficient for the start of a crop. (Note:  Not all chicken manure is approved for organic growing.)  When growing ginger in the ground, it is important to have your soil tested so you know what amendments are missing.  Also, test your ground for pH.  The pH level should be between 5.5 and 6.5.   If your soil is acidic, add dolomite 65AG (finely ground calcium and magnesium carbonate) to raise the pH and also supply calcium.  Calcium is essential for vigorous growth of ginger as it helps with the uptake of all the vitamins and minerals.  An option for calcium is gypsum.  If your soil is alkaline, add sulfur.   Areas with high rainfall tend to be acidic, and areas with less rainfall tend to be alkaline.   Wherever you live, you can go to your Cooperative Extension Service through your University for help on how much lime or sulfur to add to correct a pH balance. 

Half pound of fertilizer per square foot of bed works well at the beginning.   To prevent the risk of fertilizer burn, let the product mellow in the soil for a week or two before the seed is added.   Each grower’s fertilization requirements will vary, depending upon the soil where crops are grown.   That is why it is a wonderful idea to have your soil tested.

If the ginger is transplanted into soil with temps less than 55-60 degrees, their growth will slow way down and possibly die.  Cheap soil probes placed in several spots are very handy to determine soil temps.   Inexpensive models can be found on Amazon.  To increase soil temps earlier, use row covers placed on the rows where ginger will be planted.  Planting ginger in a hoop house/high tunnel is ideal on the mainland.

Your rows should be 3 to 4 feet apart, and beds/rows should be 3 feet on center.   Plant the ginger in the center of the bed at the bottom of a 6 inch trench (6 inches measured from original soil level).  Leave enough soil on the sides of the trench to hill later.  Eventual hilling totals about 12 inches.

Combine fertilizers and/or compost in the bottom of trench.   Also, add slow-release fertilizer (example would be 4-6-4 Sustane) and an inoculant.   Ginger sprouts or seed pieces (if you do not pre-sprout) should be about 5 inches apart (rate is about 30 lbs per 100 feet = about 1 seed piece per 5 inches on center) in the bottom of the trench.

Cover sprouts or seeds with about  3 to 4 inches of soil.   Also apply your fertilization application at this time.

As the shoot grows, check the base of the shoot(s) for swelling and a pretty pink color – this will take anywhere from 4-6 weeks.  When you see the pink, hill the crop with about 6 inches of soil and fertilize again.    Each time you see the new pink rhizome growth, hill and fertilize again.  This might happen every 2 months.    Baby ginger will be ready for harvest when the ginger is 6 months.   That is 6 months from pre-sprout to harvest or six months after the seed is in the ground. When you see pink swelling at the based of the leaf stalk, it is time for hilling.  Hill with compost or a good quality soil mixture, etc.  Hilling is covering the base of the leaf stalks with compost, etc.   In the fields, a high-speed tiller throws soil from between the rows onto the base of the stalk.   Putting the fertilizer right at the base of the stalk puts the fertilizer right where the plants can use it.   Each time you hill, add slow-release fertilizer (example would be 4-6-4 Sustane) and an inoculant.

It is important that you keep the beds of ginger evenly moist.  If your plants are overwatered, you will just wash away your fertilizer.    The ginger will become established when one shoot after another emerge from the pieces.  Healthy ginger will grow exponentially once established.  

Special Note:  The pathogen, Ralstonia solanacearum (bacterial wilt) that has plagued the ginger producers in the world can be transmitted through infected seed and poor sanitation.   Your soil may not have it now so to keep it free by planting clean bacterial-wilt-free seed.  

Bleach can be used to sterilize the surface of ginger seeds: dip them in a 10% bleach solution (1 part commercial bleach to 9 parts water) for 10 minutes. However, this may not eliminate bacterial infections within the rhizomes. A hot water treatment, consisting of exposing seeds to a constant 50°C or 122 degrees for 10 minutes, is effective in controlling nematodes but may not be effective for disease organisms such as R. solanacearum that are already present inside the rhizome.
That being said, it is so important to have sanitary growing conditions from field to field to keep your yield high and productive.

We have had tremendous support from our Cooperative Extension Service in Hilo, HI.   Without the clean seed project, all these seeds would not be available. 

Please copy and paste this website into your browser for more useful information:
http://www.ctahr.hawaii.edu/oc/freepubs/pdf/PD-99.pdf.