Great weather news (and your garden questions answered)

By Steve Reiners, Professor and Chair, Horticulture Section, School of Integrative Plant Science, Cornell University, Cornell AgriTech. 
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May 17, 2021

I’ll start off with the great news.  Based on both the calendar and the long-range weather forecast – which predicts overnight lows mostly in the 50Fs, I think we can safely  assume we are done with frosts until fall in our region.  Our normal last frost date is about May 20.  Soils are still a bit cool but warming, up close to five degrees in the last week to about 55F.  No need to rush things. But all our heat-loving crops can likely be safely planted now.

I thought it would be fun to answer a few questions I’ve received recently.

I keep hearing about cicadas and locusts arriving this summer.  How do I keep them out of my vegetable garden?

There has been a lot in the news the last month about the arrival of the 17-year, Brood-X cicadas.  These insects have been living underground feeding on tree roots since 2004 and are already emerging.  The good news is that the cicadas are not in upstate New York.  We don’t have that particular brood here.  The epicenter is in the mid-Atlantic region, around Washington DC.  We don’t expect them to be any closer than central Pennsylvania.

Even if they were coming here, they likely would leave your vegetables alone.  They typically feed on deciduous trees and shrubs, sucking plant sap from stems of woody plants, similar to aphids. 

Eventually, they lay their eggs in twigs.  The eggs hatch and the tiny nymphs fall to the ground, burrow into the soil and start the cycle again.  They’ll be back in 2038.

Our brood in upstate New York is on a different cycle and was last seen in 2018.  They are due back in 2035.

I’m confused about ‘days to harvest’ (DTH) listed with vegetables.  I planted snap beans in my garden and the packet said they will be ready in 60 days.  I transplanted tomatoes at the same time, and it says they will be ready in 82 days.  I started my tomatoes 6 weeks ago, indoors, which means they have already been growing 42 days.  Can I expect to get tomatoes in 40 days (82-42=40)?

It can be confusing.  For your tomatoes, just like any vegetable that is typically transplanted (peppers, eggplant, etc.), the DTH refers to the number of days from when you transplant in the garden.  For vegetables typically direct-seeded, like beans, peas and sweet corn, the DTH starts when you plant the seed in the garden.

Either way, DTH should only be used as an estimate and as a way to compare varieties for earliness.  It assumes perfect growing conditions.  That 60-day bean may take 70 days when planted now in relatively cool soils with chilly nights.  Plant the same variety in mid-June when things have warmed up, and a 60-day harvest is likely.

We just moved into a new house and much to my delight, there is a bed of asparagus.  The previous owner says the bed is about 5 years old.  I harvested a few spears already but want to know how long I should continue to harvest.  Also, when does the asparagus fern appear?

This is a great situation for you.  Asparagus is one of the few perennial vegetables and once established, a planting is typically is productive for 12 to 15 years.  Since your bed is 5 years old, you can likely harvest spears until about mid-June.  You’ll notice the spear diameter shrinking, which is a sign to stop the harvest.  When you stop harvesting, the spears continue to elongate, and the asparagus fern develops.

For a vigorous asparagus planting, it’s important that a large, photosynthetically active fern is present for at least 3 to 4 months.  The fern harvests the sunshine and converts it to sugars, starches and proteins stored in the underground crown. That energy will be used to produce next spring’s crop of spears.

If you harvest spears for a longer period, the ferns will be smaller, and the crowns will not be recharged as well.  Next year’s spears will then start off small and the eventual fern smaller as well.  You have now started the planting on a downward spiral which will be hard to recover from.

My compost pile always seems to take a long time to finish.  I’m careful in trying to balance the greens (high nitrogen) and the browns (high carbon) and I even aerate it a few times every summer.  What I get is great, but I’d like it faster.  Any ideas?

Normally I blame a slow process on three things.  Often people don’t have a good balance and have too much carbon materials and not enough nitrogen.  But it seems that’s not a problem.  The second thing is getting more air into the pile which helps the microbes breathe and multiply.  But you’re aerating it so that doesn’t seem to be a problem either.  The third issue is often overlooked, a pile that’s too dry. 

Most of us never think about watering our compost piles in the same way we do our gardens. But if the pile is dry, microbes are less active, and worms remain at the wetter lower level.

How much water to add?  Measure the square feet your compost pile takes up.  For example, my compost is about 3 feet wide and 4 feet long or 12 square feet. (The depth of the pile is not important.)

For every square foot, apply one gallon of water per week.  For mine, I need to apply about 12 gallons of water weekly if it does not rain.  Probably best to apply half twice per week.  And don’t worry about applying too much water.  Keep it wet and let me know how things look this fall.