Spring Garden Q&A

Spring gardening season is here! Horticulture Educator Vijai Pandian has answers for common spring gardening questions.

When can I harvest newly planted rhubarb?

In the second year after planting rhubarb, harvest stalks for 1-2 weeks in spring.  Beginning in the spring of the plant’s third year, you can extend the harvest for 8-10 weeks.  Select only the long, thick stalks for harvesting, and, depending on the variety, the leaf stalk size could vary from 12-24 inches.  To harvest the leaf stalk, grasp its base and pull upwards to one side or simply trim its base.  Chop off the leaf blades, as they contain a high amount of oxalic acid and should not be eaten.  Do not remove more than one-third of the leaf stalks from the plant at one time.

When can I harvest newly planted asparagus?

You can begin harvest asparagus spears in the third year after planting for about a month in spring.  Beginning the fourth year, you can harvest the spears for about 8-10 weeks.  When harvesting, select spears that are about 6-8 inches tall and have the thickness of your index finger.  Snap or cut the spear at its base near the soil line.

When is the best time to till and prep the garden soil?

Prep the garden soil when it is slightly moist.  Do not till it when the soil is wet – this can ruin the soil structure by forming numerous clods that are not good for planting. A simple way to determine the right condition for tilling is to squeeze a handful of dirt in your palm and roll it to form a ball. If it has the right moist condition, you can easily form a ball that crumbles apart when tapped.  Spread organic matter to a depth of 2-4 inches and plow it to a depth of 6 inches.  Fertilize the soil a week or two weeks prior to planting, and rake the fertilizer to a depth of 2-4 inches.  At the time of planting, rake the garden soil and level it even.

What type of soil mix should I use for raised beds?

You can use soilless or soil-based growing media for raised beds.  For soil-based media, mix good quality topsoil mixed with organic matter like compost and drainage material like perlite at a 1:1:1 ratio. Soil-based media gets compacted over time and it needs to be loosened up every spring by adding organic matters. For soilless media, mix peat, compost, and perlite at 1:1:1 ratio. Soilless media tends to be less compacted, however, it dries out faster.

How can you learn more?

  • Take one of our upcoming online gardening classes. Classes are free, but pre-registration required. For more info and to pre-register visit go.wisc.edu/sehorticulture 
    • May 16, 10.00 A.M. – Intro to Vegetable Gardening- Plan & Prep: Proper planning and prepping your garden beds plays a key role in successful gardening. In this presentation, Vijai Pandian, Horticulture Educator will be highlighting various factors in designing garden beds, developing soil structure, plant nutrients, and building raised beds.
    • May 19, 6.00 P.M. – Growing Blueberries in Containers and Trench: Blueberries are one of the most popular small fruit crops but they are a bit finicky about soil acidity level. This presentation will share some easy ways to overcome your soil acidity issues by growing in a soilless media in containers and trench systems.
    • May 23, 10.00 A.M. – Intro to Vegetable Gardening – Planting Tips: Is it warm enough to plant your tomatoes and vine crops? How far should I plant my crops? Learn some useful tips on when and how to plant tomatoes, peppers, pumpkins, sweet potatoes, and onions successfully.
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