Warm Season Vegetable Transplanting and Plant Sale Recommendation

This past week we saw a week of rain ending with snow that dropped 3.3 inches of precipitation in my Denver garden. The wet week ended May 10th with an overnight low of 31 degrees F.

Two years in a row! Tomatoes in Wall
O'Waters on May 12, 2014.

Any early-transplanted warm season vegetables required protection with Walls O'Water or second best the use of frost blankets. Even so warm season vegetables will likely be set back and take time to resume growth. Cloudy weather during the week didn't allow much solar gain for Walls O'Water.

Planting thoughts this week should take into account wet soils. Give them time to dry to a medium moisture content before transplanting or seeding. Don't walk in or work soil when wet; you will only destroy soil structure if you do. Meanwhile, consider what warm season vegetable varieties you want to plant this year.

Vegetable transplants being grown
by Denver Master Gardeners for their
May 16 and 17, 2015 sale.

I'm impressed with the wide selection of vegetable varieties offered by CSU Extension Denver Master Gardeners at their spring plant sale this coming weekend. The sale is Saturday, May 16 from 8am to 3pm and Sunday the 17th from 10am to 3pm.

Location is the Denver CSU Extension office in Harvard Gulch Park, 888 E. Iliff Ave, Denver, CO. This plant sale promises to be worth a visit and proceeds benefit CSU Denver's education programs.

Click to download and then open this file for more information and a list of varieties offered at the sale: Denver CMG Spring Plant Sale.

Hold your spring soil prep enthusiasm

If you didn’t prepare soil in the early part of March when it was dry, think twice about when to do it now. Two snowstorms on the 19th and 23rd (see raised bed photo right) each left my Denver garden with an inch of water, 2 inches total in less than a week. Heavy, spring snows can bring a lot of welcome moisture to gardens when snow melts (photo below left) but can interfere with cultivating soil.

Clay soils are especially sensitive to tilling at improper moisture content. They should be tilled at medium moisture, not too wet and not too dry. Tilling when too wet can create clods that take years to disperse on some clay soil types.

To check moisture, take a handful of soil and gently squeeze into a ball. If the ball crumbles when poked with a finger, it can be tilled. If the ball only reshapes with the pressure of poking, it’s too wet. Wait for it to dry more. With some clay soils there may be only a few days when soil is at the proper moisture content. If spring snows or rain are frequent, planting may be delayed.

Very wet soils are also easily compacted. Stay out of the garden when soil is wet. Water acts as a lubricant allowing soil particles to more easily slide over each other. Don’t compact soil that you worked so hard to make loose by walking in a wet garden.

One other moisture related matter is worth mentioning. Wet soils warm more slowly because the sun’s energy is used in evaporating water rather than in raising soil temperature. Cold soils will delay planting further.

Photo credit: Snowy spring raised bed gardens, both Carl Wilson