Digahole - A Division of the Resource Management Group, Inc.

"My Rose Seed Starting Method"
by: Henry Kuska, Zone 5, Northern Ohio

I pick the hips from the bushes when the hips have color or if it is getting near a night time low of around 25 degrees Fahrenheit (usually middle or late November). The hips are stored in zip lock type plastic bags. The name of the rose bush (if open pollinated) or the names of the two parents (if a cross) is written on the bag with a permanent ink marking pen. The bags are kept in an unheated attached garage in a plastic bucket (which has a sturdy cover to prevent mice from entering).

If the hips were green when picked, they are kept in the sealed bag until late December.

If the hips were ripe when picked, the seeds are removed from the hips as soon as I have the time. If the hips are from an important cross, I use a small steak knife to cut the hips and to remove the seeds. I use vinyl gloves to protect my hands while working with the hips (often the hip contains thin "hairs" which irritate the skin and/or gives off an orange "dye" which discolors the skin). For large batches of open pollinated hips I use a blender (slowest speed) with blades that have been wrapped with stainless steel adhesive backed tape (the tape is commercially sold for patching automobile bodies).

For batches that were cleaned with the blender, I use the following procedure to remove the pulp. I have two round wire kitchen strainers. The first with relatively large openings was sold for French fries. The second has relatively small openings. I place the large screen strainer on top of the small screen strainer. I place the ground up hips in the large screen strainer and press on the pulp with the back of a large spoon. This forces the seeds and the mashed pulp through the large screen. I then direct a stream of water through the pulp on the fine screen to remove as much small pulp as possible. For an important cross I would then use tweezers to hand pick the seeds from the remaining pulp.

For most open pollinated aged hips I put the pulp and seeds together into the enzyme soak described below (I don't have time to do a thorough job of cleaning; however, it appears that a complete cleaning is not necessary, I often get a very rapid germination from these combined seed, rotting pulp batches. I assume this is because the enzyme soak accelerated the decomposition of the germination inhibitor chemicals in the pulp and also accelerated the release of ethylene which is a germination promoter.).

Next, I soak the seeds (or, if the blender was used, seeds and pulp) for two days in a enzyme drain cleaner solution prepared by adding about 1 tablespoon of enzyme to 150 ml (about a half cup or 5 oz) of untreated well water. The enzyme drain cleaner should be one that states on the label that it will dissolve paper or includes cellulase as one of the ingredients. One tablet of bromelain can be substituted for the enzyme drain cleaner. Bromelain is a health food digestive enzyme. It has the advantage over the enzyme drain cleaner in that it does not appear to kill the seeds if the soak lasts for more than 2 days; thus, I use bromelain if the seeds are from an important cross. With bromelain I normally use a 2 or 3 day soak, but I have had success with soaks as long as 5 days.

I then rinse the seeds using a small mesh wire kitchen strainer. If the seeds were separated using a blender, the rinse also removes some additional pulp. Each set of seeds is then put into an individual clear plastic round container with a clear plastic lid (100 mm by 20 mm Petri dish). 14 containers fit into a standard seed tray. I half fill each container with normal children's play sand. A water mixture is made up by adding 5 ml of standard drugstore type 3 % hydrogen peroxide to every 95 ml of water. This water mixture is used to dampen the sand. The seeds are then placed on the moist sand. A red permanent ink making pen is used to write the desired information on the lid of the Petri dish (I use red because the Petri dishes will be placed under red light).

Four trays with 14 Petri dishes each are placed under two shop type 4 foot florescent light fixtures that contain two 40 watt standard Sylvania Gro-Lux florescent bulbs each. The bulbs are wrapped with red automobile lens repair tape (a red cellophane sheet over the trays could be used instead of the taped lights). This is done because there is a literature paper that reports that red light can increase the germination from about 20% to about 80%. I have 4 such set ups so I always have 16 trays under the red lights. The lights are controlled by a "12 hour on - 12 hour off" timer. I may change to only 3 set ups since I am finding very little germination in the last 4 trays.

Each day I remove one tray farthest to one end (called the "last" position) of the 16 trays and move up all of the other trays one position. The removed container's Petri dishes go into a refrigerator. The refrigerator is kept at about 40 degrees F and contains red LEDs to provide red light. There are always about 30 days' worth of Petri dishes in the refrigerator. Each day one tray's worth of 14 Petri dishes goes to the right bottom of the refrigerator and 14 Petri dishes (the longest in ) come out from the left top of the refrigerator. All of the Petri dishes in the refrigerator are moved up 14 positions each day. The ones coming out go to the opposite end of the heated trays (what I call the "first" position) as tray number 1. My keeping the seeds in a refrigerator for approximately 30 days is based on published embryo culture research papers that report that cooling benefits germination. I may increase the number of days in the refrigerator to 45 days as the weather warms up.

Each day I examine the 16 trays of seed containers that are under the red lights. Normally I observe some sprouting on the second or third day that the tray is out of the refrigerator. The sprouted seeds are removed from their containers with tweezers and placed in a 3 % drugstore type hydrogen peroxide solution (undiluted) for the time required to prepare the seedling label (no more than a few minutes). The sprouted seed is then placed (root downward) in a depression that I make on the surface of a 1 3/4 inch square peat pot which was filled with a commercial seed starting mix that contains a low dose of time release fertilizer, a wetting agent, and water crystals (and previously wetted with a solution prepared by mixing 5 ml of 3 % hydrogen peroxide with every 95 ml of water).

The 50 per tray peat pots are placed in a standard seed starting tray on a thin layer of a mixture of perlite and finely ground water crystals (this layer is present as a precaution in case some roots would grow through the bottom of the peat pots). After the initial watering of the mix and pots, all watering is done from the bottom by pouring the hydrogen peroxide/water mixture into the perlite-water crystal layer through an empty space in the 50 pots (I remove one of the pots when I water).

When a Petri dish has a germinated seed, it is removed from its tray and placed in the first tray in the rotation. To keep the trays full, one Petri dish from each tray preceding the one with the germination is moved up one tray.

Commercial clear plastic domes are put on the seedling trays, and two "double 40 inch florescent shop lights" with cool white or Gro-Lux Wide Spectrum bulbs are placed above the seedling trays. The trays are placed perpendicular to the direction of the horizontal shop lights so that two shop light fixtures ( 4 lights) cover 4 seedling trays. The lights are kept on 24 hours a day. The individual seedling trays are put into homemade thermostat controlled heating trays (each heating tray has a commercial 6 foot heating cable with an above 70 degree turn OFF thermostat taped to the inside bottom with duct tape. A sheet of aluminum is placed on the heating cable to help evenly distribute the heat. Another seed tray is placed on the aluminum sheet and the bottom seed tray is taped (with duct tape) to the top seed tray for rigidity (the reason for the heating set ups is that all of my germination work is done in an unheated attached sunroom). After several days I normally remove the clear plastic domes.

When the leaves of a seedling are almost touching the lights, that particular peat pot cube is removed and transplanted into a 3 inch "extra deep" peat pot that is three fourths filled with the same commercial potting soil described above. Additional potting soil is then placed around the inner pot. The 3 inch peat pots are placed into a clear plastic Rubbermaid "Big Storage Box" on a layer of perlite-water crystal mixture. The dimensions of the box are 39 inches by 16.4 inches by 9.2 inches height. Each box holds 44 of the three inch pots. After a box is filled with peat pots, perlite and/or potting soil is added to the empty spaces between the pots and the plastic walls of the box. Two sets of double light 4 foot florescent shop lights (with cool white or Gro-Lux Wide Spectrum bulbs) are placed on each box. The lights are kept on for 24 hours a day. When the plant leaves reach the lights, the lights are raised so that they are always an inch or so above the leaves. The plants are bottom watered ( no hydrogen peroxide is mixed with the water since the plants are past the danger stage of dying from damping off disease) by running water down the plastic sides into the perlite-water crystal layer. With a few of the waterings I add a commercial fertilizer with trace elements at about half the recommended concentration. It is easy to see the level of the water through the clear box sides.

Other comments:

The reasons for using moist sand instead of moist paper are: 1) that the sand changes color when drying out, 2) the root of the sprouted seed is not as easily damaged when removed from sand as when removed from paper, 3) the sand does not decompose and 4) the seeds are easily separated from the sand by using a kitchen wire strainer with a mesh large enough to pass the sand particles but not the seeds. The last is important as some seeds leach out inhibitor chemicals. A "freshen up" every once in a while gets rid of the leached out inhibitor. The leaching away of inhibitor is one of the possible reasons given for an explosion of seed germination outside after a heavy rain.

The "finely ground" water crystals were ordered from this company: http://www.digahole.com/prod_stock.htm . They have two sizes; The finely ground size is called the "lawn" size.

The lights above the seedlings are kept on continuously because it is my experience that the seedlings grow faster and thus grow out of the damping off danger zone quicker.

The lights above the Rubbermaid "Big Storage Box" are kept on continuously because I want the seedlings to flower as soon as possible. Roses are considered to be "day neutral" plants and are reported to flower earlier under continuous light.

One source for the 100 mm by 20 mm Petri dishes is http://www.daigger.com Enter the word "petri" into their search window and select "Falcon Disposable Petri Dishes". Their price is about 33 cents a dish (plus shipping). Any small clear top plastic container, such as containers for individual take home salad servings, butter tubs, etc could be used but the Petri dishes probably are the most efficient concerning refrigerator space.

The initial watering of the sand in the Petri dishes is done with the 5 ml 3 % hydrogen peroxide / 95 ml water mixture. For the rewaterings, I have not settled on a single method. I have tried using the above mixture with the thought that the oxygen generated should be beneficial to germination. I have also tried dilute bromelain solutions, solutions containing Ethephon, and solutions containing both Ethephon and nitrate. Unfortunately, I have not been able to sufficiently control the other possible variables to reach a conclusion about a "best" procedure.

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