Finally temperature may also be an issue. There was an article in Scientia Horticulturae long ago that discusses flower abortion at different temperatures. Although the model plant for this paper was different from raspberry, it is known that rapid temperature shifts can cause havoc on flower production in plants. Generally this is not an issue since raspberries generally flower in late spring through summer, but if there was a sudden temperature shift in either direction (colder or hotter) you may have an issue.

Mildew can also cause floral abortion. By chance did you notice any gray fuzz on any of the leaves last season? If you did, my recommendation would be to increase the air flow through the foliage by doing some maintenance pruning. By pruning away some of the canes, you will promote better air flow through the canopy which in turn decreases the chance of fungi infection.

Plant nutrition may also be an issue. Plants can abort their flowers if there is a boron toxicity. As random as this may sound, it actually happens more often than one would think. Also, too much nitrogen can cause a drop in flower/fruit production, but once again, this would not be manifested in a drop off of the flowers.

Another issue may be pruning, however, this is complex. Different varieties of raspberries require different types of pruning. Generally, red and yellow summer-fruiting varieties should be pruned right after harvest, whereas purple varieties should be pinched in early summer before harvest. Pinching and pruning are different and result in different outcomes. Since I am not sure which variety of raspberry you have, I cannot truly give you good advice with this issue. I may be able to help you more if you know which variety of raspberry you are growing.

Pollination could also be a factor, but once again I do not think this to be the case. Raspberries are mostly self-fertile and do not require pollinators to produce fruit. Raspberries that lacked any pollinators (bees more often than not are the pollinators) will show a reduction in the amount of drupelets per "berry". Drupelet is the name for the individual fruits...there are many drupelets per "berry". There will also be an overall decrease in the number of "berries" produced.

Another possibility is that your raspberry is getting too old to be extremely fruitful. I'm not 100% sure that this is the case however, since old age usually results in a general decrease in fruit production as opposed to global flower abortion, which it sounds like you had. Generally, canes older than 5-8 years will start to show a reduction in fruit production.

Hey Dr. Y...I have a couple of thoughts of what may have happened. First off, raspberries are known to be thirsty. Although blackberries are slightly more drought resistant, raspberries require constantly moist soil. (Also, it's very important that the soil drains quickly. Soggy soil can end up killing raspberries). If your raspberry suffered a drought during floral development, then it is possible that your raspberry could suffer from global flower abortion. In other words, all the flowers on the plant will fall off at roughly the same time.

There may also be the issue of chlorinated, fluoridated or soft water. Chlorinated water can be treated by being left out for a day or two. If you fear that you have salty water that is a result from fluoridation or soft water, you may want to purchase filtered water if you are strongly inclined to keep your Lucky Bamboo thriving. It is true that plants, including your Lucky Bamboo, need salts for nutrition, but the three previous examples provide salts that your Lucky Bamboo has a hard time dealing with. Yes, the potassium in soft water is beneficial to the plant, but a buildup of chloride can cause some problems. Other than too many salts in the irrigation water, the rootzone may be overcrowded with roots. If that's the case you may want to repot the plant. I hope this information is helpful. Please let me know if you have any further questions. Happy Gardening...Dr. Robby

Hey Richard...When Lucky Bamboo's leaves start turning brown, I generally think of one of two things. It's either getting too much light, which in your case it does not seem to be the issue; or there is something wrong with the with the rootzone. I'm thinking it's the latter of the two so I will expand upon this. Lucky Bamboo, aka Dracaena sanderiana, can be grown in standing water. Many home gardeners will simply add more water to the bowl of pebbles that the roots are sitting in. This is fine, but the bowl will need to be flushed of the water from time to time. If a gardener simply refills the bowl with water time and time again, even the use of the cleanest of tap waters will result in a salt buildup in the water. As the salt builds up, the plant will suffer. I would recommend flushing the water out from time to time by simply pouring out the standing water and replacing the water completely. I would also repeat this a number of times to leach out some of the salts.

I hope this information is helpful to you. Let me know if you have any further questions as I am always happy to help out. Cheers...Dr. Robby