Broccoli Double Vision

I've been eating lots of hefty carrots recently. This should be evident by my last blog post. Carrots contain Vitamin A, which is an essential nutrient for good vision. Despite my prodigious intake of these health-supporting wonders, I discovered that something was wrong with my eyesight this afternoon.

After lunch, I walked out into the rain to plant some radishes in my garden. I was a few feet from my potted Calabrese broccoli when I started seeing double. I could've sworn I harvested my broccoli last month, but sure enough...side shoots of broccoli had sprouted up everywhere! Double broccoli!!

Side shoots of Calabrese broccoli (left and bottom). I harvested the central head of broccoli on January 19. Notice the off-white area near the center of the picture where I cut the central head with a small knife. Exactly one month later I harvested the side shoots.

Calabrese broccoli is no one trick pony. It grows not once, but twice. Exactly one month had passed from the time of my initial harvest to today's second harvest. Here's a close-up view of some side shoots.

Secondary shoots of Calabrese broccoli growing from the side of a potted plant.

Because of my relatively care-free harvest and positive experience with broccoli this year, I am planning on growing multiple varieties next fall. In addition to Calabrese, I will be sowing seeds of Super Rapini broccoli raab and Romanesco broccoli.

Broccoli varieties for future planting at .09 Acres.

I definitely recommend home-grown broccoli for every gardener, beginner or advanced. You will be pleasantly surprised with your harvest if the plant is grown in compost-rich soil and kept moist. Here's a list of the pros and cons of growing broccoli:

PROS:

• large central heads of sweet, tender broccoli
• secondary harvest of side shoots 3-4 weeks after main harvest
• unbeatable flavor compared to insipid store-bought broccoli
• extremely tolerant of hard frosts and variable weather
• can be grown in large pots
• beautiful blue/green foliage

CONS:

• young plants are prone to attack by caterpillars
• needs steady supply of water as a seedling
• large size when mature (appx. 36" in diameter in my garden) 
• long time from seed to harvest 

Movin' On Up -- New USDA Plant Hardiness Zone Map

The USDA recently released a new Plant Hardiness Zone Map (http://planthardiness.ars.usda.gov/PHZMWeb/Default.aspx).

2012 USDA Plant Hardiness Zone Map.

What type of data is this mapped based upon, and how is it different from previous years? Here's what the USDA website states:

"Zones in this edition of the USDA Plant Hardiness Zone Map (PHZM) are based on 1976–2005 weather data. A trial check did not find that the addition of more recent years of data made a significant difference in the definition of these zones. Each zone represents the mean extreme minimum temperature for an area, calculated from the lowest daily minimum temperature recorded for each of the years 1976–2005. This does not represent the coldest it has ever been or ever will be in an area, but it simply is the average of lowest winter temperatures for a given location for this time period.

The previous edition of the USDA PHZM, revised and published in 1990, was drawn from weather data for 1974–1986. The longer period (30 years) of data was selected by the group of horticultural, botanical, and climatological experts who led the review of the latest revision as the best balance between smoothing out the fluctuations of year-to-year weather variation and the concept that during their lifetimes, perennial plants mostly experience what is termed "weather" rather than "climate."

Because this map was created digitally with GIS technology, it has a higher level of resolution and can show smaller areas of zone delineations than ever before. For example, cities tend to hold more heat because they have large amounts of concrete and blacktop, so a city or town may be assigned to a zone warmer than the surrounding countryside. Higher elevations tend to be colder than surrounding lower areas, so the top of a mountain may be an area of cooler zones. A location near a large body of unfrozen water may provide milder winter weather and be in a warmer zone."


So what does this mean for gardeners in Virginia, particularly the Tidewater area? Minor zone changes for some gardeners, probably not too much change for most other gardeners. Here is the detailed map of Virginia reflecting the above changes:

2012 USDA Plant Hardiness Zone Map for Virginia.

Many of the inland areas and some outlying coastal areas retained their previous zone designations. But it is interesting to note that GIS technology has allowed the USDA to define smaller zone delineations than in past versions of the map. 

.09 Acres is located in Newport News, Virginia, two blocks from the James River and near the end of the Virginia Peninsula. The southern exposure of my neighborhood on the north bank of the James River and warmth-retaining properties of the river and Chesapeake Bay are factors that influence my hardiness zone. In previous years, I was in Zone 7b. The new map has moved up my location a notch to 8a, reflecting these characteristics and suggesting we have slightly warmer winter lows than indicated on past USDA hardiness maps. In reality, my fenced/protected backyard is likely another half-zone or zone higher, reflecting an even more defined micro-climate.

It is important to note that there are always variations within these types of designations, but the USDA Plant Hardiness Zone Map can be a helpful general reference for gardeners. 

Did your hardiness zone remain the same or change from the past USDA map? Do you provide micro-climates for your plants to stretch the boundaries of your hardiness zone? Or do you say, "Phooey to all this this scientific mumbo jumbo! Mother Nature does what she wants and I have no control over her whims. This arbitrary designation doesn't mean a thing to me or my plants."

I'm looking forward to hearing your thoughts.