Saturday, November 19, 2011

How do I get my Hydrangea to bloom? Had it 8 years and only bloomed once. HELP!!?

The plants are large and green and healthy, just never blooms

How do I get my Hydrangea to bloom? Had it 8 years and only bloomed once. HELP!!?
Hydrangeas of any species should be planted in the spring time after the fear of last frost or in the fall well before the night time temperatures flirt with 32 degrees. If planting in the fall you should avoid high doses of fertilizer as you do not want soft growth while entering into winter. You are best off using a water soluble fertilizer at ¼ strength and only apply it twice after fall planting. Planting of hydrangeas should be done 45-60 days before the first expected freeze.

The soil should be rich in organic matter and drain well. Avoid planting in highly sandy soils and heavy clay soil. Amend the sandy soil with aged compost and only plant on or near clay if the water will drain away.

Feed your hydrangeas! Hydrangeas are greedy plants and do best when fed enough during the early to middle part of the growing season. I suggest a slow release fertilizer such as Osmocote slow release with minors. An N-P-K ratio of 10-10-10 is fine. This feed can be purchased through my website or at home depot for roughly $5.00 per pound. Aged manure is excellent for adjusting your soil but has a very small kick as far as the N-P-K requirements are concerned. Using aged manure (fresh manure will burn plants) in combination with a slow release fertilizer is ideal if your soil is poor to begin with.

I can't state enough the importance of regular irrigation both after planting and 5 years later even after the hydrangea is established. Newly planted hydrangeas should be watered well once a day if planted in a shadier spot and twice a day if planted in more sun for the first two to three weeks. Really babying them pays off. Established plants really shine if pampered with regular irrigation. I have my display garden on a daily watering cycle for the first half of the growing season and every third day after the heat of August has passed. I stop irrigating and let nature take over in early September.

Propagating hydrangeas top

Hydrangeas are one of the easiest shrubs to duplicate by tip cuttings and layering. Both techniques will be described below starting with tip cuttings.

Take a 4-6" cutting from the tip of a hydrangea in active growth. Rapid growing stems (soft wood) make for better cuttings than late season (semi hard wood) cuttings do. The cutting should have 4-6 sets of bud axilles with the cut in the stem

Remove the foliage from the bottom set of buds and cut the top leaves in half. By removing the bottom foliage and reducing the top foliage by ½, you will be limiting the surface area from which moisture can be removed from the cutting.

Prepare your soiless medium. I use 70% perlite and 30% peat moss. Mix the two products together and fill in your rooting container. You can use a small plastic pot or any type of small container that has a drainiage hole in it. Soak the medium and allow the water to run off.

Dip the cutting in rooting hormone if desired (I don't use the rooting hormone as it is not necessary for hydrangeas) the hormone will increase the rooting time by 5-7 days. Using a pencil, dibble a hole in your rooting medium and place the cutting in roughly 2" and softly pack the medium back in and around the hydrangea stem.

Place the container in an area where there will be no direct light, no wind and no heavy shade. Some people place the container in a clear plastic bag with coat hangers or wood sticks fashioned as a mini greenhouse. This process locks in moisture and also raises the temperature. 70-75 degrees is perfect for successful rooting. Too high of a temperature will cook your cuttings and too low of a temperature will slow the rooting process allowing all of the possible mis-haps to occur while struggling to form roots.

That first soaking should last for a while. Do not overwater. Once the top of the rooting medium looks like it is starting to dry out you can apply more water. Too much water will rot your cuttings and too little water will cause the leaves to droop and eventually die out. In the correct environment, your cuttings should root out in 3-5 weeks depending on weather or not you used a rooting hormone. Tugging on the cutting lightly in three weeks time you may feel some resistance. Wait 3-5 more days and transplant to a larger container. If the cutting pops right up, just leave it alone and check it out in another week. Once transplanted, do not allow the cutting to be placed in direct all day sun. For the first few days place the new plant in morning sun for an hour or so and increase the exposure an hour every day after the first three days by an hour until the plant is able to adjust itself to the full exposure.

1st year hydrangeas should not be expected to overwinter in a frozen state. They must be babied a bit and not allowed to freeze solid as this will more than likely kill them. I have killed thousands of cuttings in the past. Failure is ok as you must try again. In the north, you must place the hydrangea in an area where it will not freeze. After the first winter has passed there is usually enough mass to the stems to survive the second winter exposed to the elements.

Layering hydrangeas top

Working with an existing hydrangea already planted in your landscape or a freshly planted hydrangea of your choosing, layering is an easy and more successful method of propagating then is softwood tip cuttings as previously written about. Each method has it's own benefits. When using the tip cutting method you can reproduce 100's even 1000's of hydrangea cuttings in a relatively small space. When propagating by the layering method you can only get a few plants per stem. While tip cuttings need an aftificial environment to survive, the layering method can be done right there in the natural setting.

Pick a hydrangea shrub in late spring to early summer that has fresh stem growth (green stems). Pull an outside stem to the ground making sure that it will reach and can actually be bent a little further down. Measure out a 6-12" section of the stem that you know will be underground (this is determined when you bend the stem over at the beginning) and mark the beginning and end with a pen or marker.

Make a cut 1/8th of an inch deep and an inch long and leave it attached on one end or just simply make a scratch in the stem an 1/8th of an inch deep and an inch long. Both methods accomplish the same thing. When you injure a hydrangea stem the plants survival instinct takes over and speeds up the rooting process.

Assuming that the surrounding garden soil is good, dig a pre-alligned 6-12" trench that is roughly 2-3" deep.

Pull the ready stem over and press it against the bottom of the trench while backfilling the trench with the other hand firmly packing the soil down. Water well. Place a brick or rock over the buried stem and forget about it and go on to another hydrangea. 1 shrub can produce many new plants this way. Every stem can be used without doing any harm to the plant.

Even though the stem will root out in 1-2 months you are best off leaving it right there until the following spring. Your first thought is "who wants to wait that long"? but since you can't leave a first year tip cutting out during the winter anyway, you can leave a first year layered hydrangea stem out during the winter as long as it is still attached to the mother plant. When you dig the new plant up in the spring you will have very strong shrub that will grow rapidly and more than likely flower the first season.

In the spring dig a small hole around the stem back closer to the mother plant and make a cut in the stem with pruners seperating your new hydrangea from the mother. With a small hand shovel, dig out a 6-8" wide and deep circular hole around the stem and pull up your prize and be ready to transplant to a pot or another are in the garden.

If you have the room and long enough canes on your hydrangea you may do what is called the serpintene method where you burry the lower section as decribed before in the layering method of propagation and bring the stem back up again and down again and back up once. This allows you to produce two plants out of one stem.

Pruning hydrangeas top

There has been much confusion over the years about when to prune or not prune. To make it as simple as possible each species will be listed below along with the correct method for pruning that particular species.

Macrophylla (mophead)

Roughly 98% of hydrangea macrophylla flowers off of old wood. This means that next years flowers are being formed on this years branches. The flowers for next season are usually being formed during and after flowering. My advice is to not prune this species but to purchase the right size variety for the particular area to be planted. Don't buy a 6' tall and wide Nikko Blue to go under a 4' window box. There are so many varieties available that you should be able to find a suitable hydrangea for even the smaller areas of your landscape. A general rule of thumb is the further down you prune a hydrangea macrophylla, the less flowers will form the following season. The other 2% that are the exception to this rule are hydrangea macrophylla 'Endless Summer, 'Penny Mac' and 'All Summer Beauty'. These fantastic varieties flower off of new wood as well as old wood. No matter if you have a severe winter or late frost that would normally damage flower buds, the new growth will contain flower buds that can't be destroyed unless you dry the plant out severely.

Serrata, involucrata and aspera

These species should be treated the same as macrophyllas as far as pruning is concerned. Choose the hydrangea with the ultimate finished height and spread in mind and don't prune to make a hydrangea fit an area that is too small.

Paniculata and arborescens

Both of these species of hydrangea flower off of new growth. Pruning is suggested. While you don't have to be quite this exacting, the following guidelines are what I suggest for best results. In the early spring, before new growth emerges past 2-3 inches, prune your pee gees and or arborescens in half. If the shrub is 4' tall, prune down to 2' tall. This encourages vigorous growth and great structure. You may prune all the way down to 6" nubs if you wish. This will cause rapid growth and enormous flowers which will usually flop over in high wind or the first heavy rain. No pruning at all will result in less vigorous growth and smaller flowers. I have found that pruning down by ½ of the previous seasons growth to be the happy medium. An old overgrown pee gee that is not performing may need to be severely pruned down hard to encourage new shoots and rejuvenate the entire plant.

Anomala petiolaris

Climbers do not need to be pruned. Their growth tends to seem stunted in the early stages however, rapid growth will ensue after the 3rd or 4th year. Pruning can be done if you wish to stop a certain direction of growth.

Altering the flower color of hydrangeas top

The most exciting aspect of hydrangeas is the wide array of beautiful flowers in so many different colors and shades. The fact that you can manipulate the colors only adds to the overall attraction of these garden treasures. There are many different tricks one can use to alter flower color such as pennies and nails stuck in the soil but I will keep it simple and just suggest one recipe for blueing hydrangeas and one for making the flower color lighter or pinker. To go from dark blue or purple to pink and or from pink to blue or purple can take from 3-6 months depending on the soils ph and the amount of aluminum present in the soil. Be patient and plan ahead. Knowing the pH of your soil is helpful but not necessary. Most growers will grow their hydrangeas in a soil that is slightly acidic to near neutral because this is where hydrangeas will take up the most nutrients and perform the best as far as growth is concerned. This is the reason why you may have purchased a specific variety of hydrangea in the past with a certain color in mind only to have the blue hydrangea open pink. If you know your soil is generally acidic then you will need to apply the aluminum sulphate lightly, roughly ½ as often as I recommend for a neutral soil. Dropping your soils pH too far can result in reducing your plants ability to take up nutrients causing poor performance and even death. Don't apply more aluminum sulphate than is recommended.

To blue your hydrangea

In a 1 gallon watering can filled with warm water mix in 1 heaping tablespoon of aluminum sulphate and stir well until the crystals are disolved. Avoiding the foliage, apply the entire gallon of solution slowly to the ground on and around the hydrangea. I water the hydrangea 1 hour before applying aluminum sulphate. This helps to avoid run off of the solution. I then pour one half of the solution and wait a few minutes before applying the rest. Start this application in early spring, before active growth if you need to play catch up, and repeat every 20-30 days until flowering. Once the flowers open you will be able to determine weather or not the desired results have been reached. If not, continue to apply the solution through the flowering of the plant and twice after the flowers have finished. After this you should stop for the winter and start in again in the spring. If you were close to the desired color the year before then you should only apply the solution every 35-40 days until flowering occurs. To maintain that level of pH, you will only need to apply aluminum sulphate 3 times a year or less after reaching the correct level. A pH tester can be purchased at home depot or any garden center and is really useful in determining when and how much aluminum sulphate to apply. You can also purchase aluminum sulphate at home depot as well. I also offer aluminum sulphate through the website and can ship it to arrive with your plants. The desired pH level for blueing hydrangeas is somewhere in the low 5's. 5.2-5.8 is where I experience great blues and purples. Fertilizer does have slight effects on the overall results but, if an even fertilizer is used, The desired results can be achieved without confusing things any further.

To lighten or pink a hydrangea

Success in doing this will depend on the variety of hydrangea as some varieties will simply not lighten to pink. You will also need to raise the pH. In doing this you will stop the hydrangea from taking up any naturally occuring aluminum present in the soil and therefore, stopping the blueing process. Lime is the best way for the home owner to raise the pH level. Add dolomitic lime 3-4 times a year starting in the early spring or even the previous fall. Applying a fertilizer high in phosphorus will aid in keeping aluminum out of your hydrangeas system. On the bag you will see the n-p-k ratio. Phosphorus is the middle number. You will want a fertilizer with an elevated level of phosphorus such as 10-20-10. Foundation plantings are often exposed to higher levels of lime due to the cement foundation itself leaching it out over time. If you are planting up next to the house, you may not need to add anything to the soil for pink flowers. Remember, some varieties will not go pink. In each description of the varieties that I offer I state the color range you will experience.

Transplanting hydrangeas top

The best time to transplant hydrangeas is when the hydrangea is dormant. During this period, you may transplant at any time. Even a mature shrub will need to be babied after transplanting. Irrigate as you would any newly planted shrub. Dig as large a rootball as you think you can handle while leaving fully grown hydrangea transplanting to a landscaper or gardener. The larger the rootball, the less stress and root disturbance will occur resulting in a higher rate of success. If you must move hydranges during the spring or fall after active growth has begun, you can call me toll free at 1-888-642-1333 and we can discuss your individual circumstances to determine the best plan of attack. During this time success rates drop sharply.

Why won't my hydrangeas bloom? top

There are many reason for a hydrangea to fail to bloom. I will start with the most common reasons and go from there.

I have found that the most common reason for lack of blooms is pruning at the wrong time during the season and eliminating the flower buds. My advice is to not prune your hydrangeas other than simple removal of spent flowers which will be pruned off just below the flower itself at the next lower set of buds. You may prune the tops of your hydrangeas after the active growth begins in spring and it is obvious what is dead and what is not. Be careful because even now I am still speculating that certain buds are dead only to notice a few weeks later that the bud I thought was dead is now a stem in active growth. Remember that paniculatas and arborescens can be pruned as they flower off of new growth. There are also some varieties of macrophylla that bloom off of new wood and can be pruned in late season. Those varieties are 'All Summer Beauty', 'Penny Mac' and 'Endless Summer'. It is these hydrangeas that are confusing everybody as to what, when and where to prune or not prune. Don't put yourself in a situation where you are forced to prune. Be patient in the spring and wait for all buds to return before pruning the tips.

Too cold of a climate for successful hydrangea flowering. If you are in zone 5 you will not have luck with 95% of the available mopheads on the market. If your neighbors do not have hydrangeas, other than pee gees or annabelles, you are more than likely in too cold of an area for successful bud return. What confuses things is that the climate seems to be changing and zone lines may shift from year to year. We also are experiencing el nino every 7 years or so and this is causing variations in our winters from mild one year to severe the next year. While the hydrangeas will grow like crazy and give you lots of great foliage, the buds will always burn in a normal zone 5 winter.

Planted in heavy shade. Too much shade can be a cause of non flowering simply because of the lack of energy from the sun. You will notice less flowers gradually as the years go on. Transplant to a sunnier location.

Severe dry spells the season before can and does cause the hydrange to not flower. This can be avoided by choosing a location that is not too sunny and by adding some sort of irrigation system.

While some soils can be so poor as to cause growth and flowering problems, the above 4 reasons are the main causes of a non flowering hydrangea.
Reply:Contact your local garden center. i believe they are acid loving and require acid to bloom. I just can't be sure though. Most garden centers or landscape centers will have the answer for you.

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