Disease on Transplants

Many of our new gardeners have asked if we could show them what diseased transplants look like to prevent them from purchasing what may turn into a problem.  With so many getting their beds ready for the fall I thought it would make an excellent post for us all.

Early stage of disease on broccoli transplants!

I did a little recon mission this past weekend (sunglasses and all) and the photo to the right shows "Arcadia" broccoli plants available at a local retailer.  I did not put a name to the retailer, as right next to the diseased broccoli was some of the most beautiful red cabbages that would make a wonderful addition to anyone's fall garden.

Several of the broccoli plants pictured show the early stage of disease present.  If you blow the photo up it is easy to see the spots located on the lower leaves.  A pale colored leaf or one that is solid yellow can be somewhat benign, although not always.  Often, it can be signs of something as simple as inappropriate watering practices or a nutrient deficiency.  The fix would then be rather easy to take care of by either correcting the watering habits of the plant or fertilizing appropriately.  However, when plants have leaves that are off in color and accompanied by spots, it is most often a symptom or sign of disease. 

Unfortunately, these plants would require the use of fungicides on an on-going basis much as you have experienced with your tomatoes.  The disease is not curable.  All parts of a broccoli plant are edible.  The stalk, leaves, final head, and any side shoots they produce.  Having a plant that is infected with disease early on will reduce the amount you are able to get back out of your garden for the money, time, and effort you have put in.  Diseased leaves do not have the eating quality you desire and the disease will spread throughout the garden infecting other plants within that same vegetable family.

Arcadia Broccoli and Dino Kale!

Now let us look at this other photo.  In the upper left-hand corner, you will see the same cultivar of broccoli growing from a healthy transplant.  This photo is from late September of last year.  Notice the absence of any yellowing or spots on the leaves. Starting with a healthy transplant reduces the need for fungicides and the eating quality, therefore, is greatly increased.  This allows you to get more back out of your garden for the expense and effort put in.  In addition, plants that remain healthy are less likely to be attacked by insects or the damage from these pests will most often be insignificant or easily controlled.

These plants were treated with a compost tea solution at planting and then twice per month thereafter. They did not receive or require any additional fertilization.  A fungicide was required only three times throughout their growing cycle due to excessive rains causing an outbreak of downy mildew in the garden. After harvesting the central heads, the plants continued to produce side shoots well into April when they were pulled to make way for the next season of growing.

By being able to recognize transplants that have disease already present, we should be able to avoid some of the diseases that come into the garden via this avenue.

Happy Gardening,

Denise, Beds 25 & 29